2025-05-04 10:33:46 +01:00
329 changed files with 10165 additions and 29499 deletions
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@ -46,9 +46,9 @@ jobs:
    - name: make cli
      run: |
         make -j2 config=sanitize werror=1 luau luau-analyze luau-compile # match config with tests to improve build time
-         ./luau tests/conformance/assert.luau
-         ./luau-analyze tests/conformance/assert.luau
-         ./luau-compile tests/conformance/assert.luau
+         ./luau tests/conformance/assert.lua
+         ./luau-analyze tests/conformance/assert.lua
+         ./luau-compile tests/conformance/assert.lua

  windows:
    runs-on: windows-latest
@ -81,12 +81,12 @@ jobs:
      shell: bash # necessary for fail-fast
      run: |
        cmake --build . --target Luau.Repl.CLI Luau.Analyze.CLI Luau.Compile.CLI --config Debug # match config with tests to improve build time
-        Debug/luau tests/conformance/assert.luau
-        Debug/luau-analyze tests/conformance/assert.luau
-        Debug/luau-compile tests/conformance/assert.luau
+        Debug/luau tests/conformance/assert.lua
+        Debug/luau-analyze tests/conformance/assert.lua
+        Debug/luau-compile tests/conformance/assert.lua

  coverage:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-20.04 # needed for clang++-10 to avoid gcov compatibility issues
    steps:
    - uses: actions/checkout@v2
    - name: install
@ -94,7 +94,7 @@ jobs:
        sudo apt install llvm
    - name: make coverage
      run: |
-        CXX=clang++ make -j2 config=coverage native=1 coverage
+        CXX=clang++-10 make -j2 config=coverage native=1 coverage
    - name: upload coverage
      uses: codecov/codecov-action@v3
      with:
--- a/.github/workflows/new-release.yml
+++ b/.github/workflows/new-release.yml
@ -29,8 +29,8 @@ jobs:
  build:
    needs: ["create-release"]
    strategy:
-      matrix: # not using ubuntu-latest to improve compatibility
-        os: [{name: ubuntu, version: ubuntu-22.04}, {name: macos, version: macos-latest}, {name: windows, version: windows-latest}]
+      matrix: # using ubuntu-20.04 to build a Linux binary targeting older glibc to improve compatibility
+        os: [{name: ubuntu, version: ubuntu-20.04}, {name: macos, version: macos-latest}, {name: windows, version: windows-latest}]
    name: ${{matrix.os.name}}
    runs-on: ${{matrix.os.version}}
    steps:
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@ -13,8 +13,8 @@ on:
 jobs:
  build:
    strategy:
-      matrix: # not using ubuntu-latest to improve compatibility
-        os: [{name: ubuntu, version: ubuntu-22.04}, {name: macos, version: macos-latest}, {name: windows, version: windows-latest}]
+      matrix: # using ubuntu-20.04 to build a Linux binary targeting older glibc to improve compatibility
+        os: [{name: ubuntu, version: ubuntu-20.04}, {name: macos, version: macos-latest}, {name: windows, version: windows-latest}]
    name: ${{matrix.os.name}}
    runs-on: ${{matrix.os.version}}
    steps:
--- a/Analysis/include/Luau/AnyTypeSummary.h
+++ b/Analysis/include/Luau/AnyTypeSummary.h
@ -0,0 +1,148 @@
+// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
+#pragma once
+
+#include "Luau/AstQuery.h"
+#include "Luau/Config.h"
+#include "Luau/ModuleResolver.h"
+#include "Luau/Scope.h"
+#include "Luau/Variant.h"
+#include "Luau/Normalize.h"
+#include "Luau/TypePack.h"
+#include "Luau/TypeArena.h"
+
+#include <mutex>
+#include <string>
+#include <vector>
+#include <optional>
+
+namespace Luau
+{
+
+class AstStat;
+class ParseError;
+struct TypeError;
+struct LintWarning;
+struct GlobalTypes;
+struct ModuleResolver;
+struct ParseResult;
+struct DcrLogger;
+
+struct TelemetryTypePair
+{
+    std::string annotatedType;
+    std::string inferredType;
+};
+
+struct AnyTypeSummary
+{
+    TypeArena arena;
+
+    AstStatBlock* rootSrc = nullptr;
+    DenseHashSet<TypeId> seenTypeFamilyInstances{nullptr};
+
+    int recursionCount = 0;
+
+    std::string root;
+    int strictCount = 0;
+
+    DenseHashMap<const void*, bool> seen{nullptr};
+
+    AnyTypeSummary();
+
+    void traverse(const Module* module, AstStat* src, NotNull<BuiltinTypes> builtinTypes);
+
+    std::pair<bool, TypeId> checkForAnyCast(const Scope* scope, AstExprTypeAssertion* expr);
+
+    bool containsAny(TypePackId typ);
+    bool containsAny(TypeId typ);
+
+    bool isAnyCast(const Scope* scope, AstExpr* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    bool isAnyCall(const Scope* scope, AstExpr* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+
+    bool hasVariadicAnys(const Scope* scope, AstExprFunction* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    bool hasArgAnys(const Scope* scope, AstExprFunction* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    bool hasAnyReturns(const Scope* scope, AstExprFunction* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+
+    TypeId checkForFamilyInhabitance(const TypeId instance, Location location);
+    TypeId lookupType(const AstExpr* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    TypePackId reconstructTypePack(const AstArray<AstExpr*> exprs, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+
+    DenseHashSet<TypeId> seenTypeFunctionInstances{nullptr};
+    TypeId lookupAnnotation(AstType* annotation, const Module* module, NotNull<BuiltinTypes> builtintypes);
+    std::optional<TypePackId> lookupPackAnnotation(AstTypePack* annotation, const Module* module);
+    TypeId checkForTypeFunctionInhabitance(const TypeId instance, const Location location);
+
+    enum Pattern : uint64_t
+    {
+        Casts,
+        FuncArg,
+        FuncRet,
+        FuncApp,
+        VarAnnot,
+        VarAny,
+        TableProp,
+        Alias,
+        Assign,
+        TypePk
+    };
+
+    struct TypeInfo
+    {
+        Pattern code;
+        std::string node;
+        TelemetryTypePair type;
+
+        explicit TypeInfo(Pattern code, std::string node, TelemetryTypePair type);
+    };
+
+    struct FindReturnAncestry final : public AstVisitor
+    {
+        AstNode* currNode{nullptr};
+        AstNode* stat{nullptr};
+        Position rootEnd;
+        bool found = false;
+
+        explicit FindReturnAncestry(AstNode* stat, Position rootEnd);
+
+        bool visit(AstType* node) override;
+        bool visit(AstNode* node) override;
+        bool visit(AstStatFunction* node) override;
+        bool visit(AstStatLocalFunction* node) override;
+    };
+
+    std::vector<TypeInfo> typeInfo;
+
+    /**
+     * Fabricates a scope that is a child of another scope.
+     * @param node the lexical node that the scope belongs to.
+     * @param parent the parent scope of the new scope. Must not be null.
+     */
+    const Scope* childScope(const AstNode* node, const Scope* parent);
+
+    std::optional<AstExpr*> matchRequire(const AstExprCall& call);
+    AstNode* getNode(AstStatBlock* root, AstNode* node);
+    const Scope* findInnerMostScope(const Location location, const Module* module);
+    const AstNode* findAstAncestryAtLocation(const AstStatBlock* root, AstNode* node);
+
+    void visit(const Scope* scope, AstStat* stat, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatBlock* block, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatIf* ifStatement, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatWhile* while_, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatRepeat* repeat, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatReturn* ret, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatLocal* local, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatFor* for_, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatForIn* forIn, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatAssign* assign, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatCompoundAssign* assign, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatFunction* function, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatLocalFunction* function, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatTypeAlias* alias, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatExpr* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatDeclareGlobal* declareGlobal, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatDeclareClass* declareClass, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatDeclareFunction* declareFunction, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+    void visit(const Scope* scope, AstStatError* error, const Module* module, NotNull<BuiltinTypes> builtinTypes);
+};
+
+} // namespace Luau
--- a/Analysis/include/Luau/AutocompleteTypes.h
+++ b/Analysis/include/Luau/AutocompleteTypes.h
@ -57,7 +57,7 @@ struct AutocompleteEntry
    // Set if this suggestion matches the type expected in the context
    TypeCorrectKind typeCorrect = TypeCorrectKind::None;

-    std::optional<const ExternType*> containingExternType = std::nullopt;
+    std::optional<const ClassType*> containingClass = std::nullopt;
    std::optional<const Property*> prop = std::nullopt;
    std::optional<std::string> documentationSymbol = std::nullopt;
    Tags tags;
@ -85,7 +85,7 @@ struct AutocompleteResult
 };

 using StringCompletionCallback =
-    std::function<std::optional<AutocompleteEntryMap>(std::string tag, std::optional<const ExternType*> ctx, std::optional<std::string> contents)>;
+    std::function<std::optional<AutocompleteEntryMap>(std::string tag, std::optional<const ClassType*> ctx, std::optional<std::string> contents)>;

 constexpr char kGeneratedAnonymousFunctionEntryName[] = "function (anonymous autofilled)";

--- a/Analysis/include/Luau/BuiltinDefinitions.h
+++ b/Analysis/include/Luau/BuiltinDefinitions.h
@ -70,7 +70,6 @@ Property makeProperty(TypeId ty, std::optional<std::string> documentationSymbol
 void assignPropDocumentationSymbols(TableType::Props& props, const std::string& baseName);

 std::string getBuiltinDefinitionSource();
-std::string getTypeFunctionDefinitionSource();

 void addGlobalBinding(GlobalTypes& globals, const std::string& name, TypeId ty, const std::string& packageName);
 void addGlobalBinding(GlobalTypes& globals, const std::string& name, Binding binding);
--- a/Analysis/include/Luau/Clone.h
+++ b/Analysis/include/Luau/Clone.h
@ -4,7 +4,6 @@
 #include <Luau/NotNull.h>
 #include "Luau/TypeArena.h"
 #include "Luau/Type.h"
-#include "Luau/Scope.h"

 #include <unordered_map>

@ -27,22 +26,13 @@ struct CloneState
 * while `clone` will make a deep copy of the entire type and its every component.
 *
 * Be mindful about which behavior you actually _want_.
- *
- * Persistent types are not cloned as an optimization.
- * If a type is cloned in order to mutate it, 'ignorePersistent' has to be set
 */

-TypePackId shallowClone(TypePackId tp, TypeArena& dest, CloneState& cloneState, bool ignorePersistent = false);
-TypeId shallowClone(TypeId typeId, TypeArena& dest, CloneState& cloneState, bool ignorePersistent = false);
+TypePackId shallowClone(TypePackId tp, TypeArena& dest, CloneState& cloneState);
+TypeId shallowClone(TypeId typeId, TypeArena& dest, CloneState& cloneState);

 TypePackId clone(TypePackId tp, TypeArena& dest, CloneState& cloneState);
 TypeId clone(TypeId tp, TypeArena& dest, CloneState& cloneState);
 TypeFun clone(const TypeFun& typeFun, TypeArena& dest, CloneState& cloneState);
-Binding clone(const Binding& binding, TypeArena& dest, CloneState& cloneState);
-
-TypePackId cloneIncremental(TypePackId tp, TypeArena& dest, CloneState& cloneState, Scope* freshScopeForFreeTypes);
-TypeId cloneIncremental(TypeId typeId, TypeArena& dest, CloneState& cloneState, Scope* freshScopeForFreeTypes);
-TypeFun cloneIncremental(const TypeFun& typeFun, TypeArena& dest, CloneState& cloneState, Scope* freshScopeForFreeTypes);
-Binding cloneIncremental(const Binding& binding, TypeArena& dest, CloneState& cloneState, Scope* freshScopeForFreeTypes);

 } // namespace Luau
--- a/Analysis/include/Luau/Constraint.h
+++ b/Analysis/include/Luau/Constraint.h
@ -50,7 +50,6 @@ struct GeneralizationConstraint
    TypeId sourceType;

    std::vector<TypeId> interiorTypes;
-    bool hasDeprecatedAttribute = false;
 };

 // variables ~ iterate iterator
@ -110,21 +109,6 @@ struct FunctionCheckConstraint
    NotNull<DenseHashMap<const AstExpr*, TypeId>> astExpectedTypes;
 };

-// table_check expectedType exprType
-//
-// If `expectedType` is a table type and `exprType` is _also_ a table type,
-// propogate the member types of `expectedType` into the types of `exprType`.
-// This is used to implement bidirectional inference on table assignment.
-// Also see: FunctionCheckConstraint.
-struct TableCheckConstraint
-{
-    TypeId expectedType;
-    TypeId exprType;
-    AstExprTable* table = nullptr;
-    NotNull<DenseHashMap<const AstExpr*, TypeId>> astTypes;
-    NotNull<DenseHashMap<const AstExpr*, TypeId>> astExpectedTypes;
-};
-
 // prim FreeType ExpectedType PrimitiveType
 //
 // FreeType is bounded below by the singleton type and above by PrimitiveType
@ -289,8 +273,7 @@ using ConstraintV = Variant<
    UnpackConstraint,
    ReduceConstraint,
    ReducePackConstraint,
-    EqualityConstraint,
-    TableCheckConstraint>;
+    EqualityConstraint>;

 struct Constraint
 {
--- a/Analysis/include/Luau/ConstraintGenerator.h
+++ b/Analysis/include/Luau/ConstraintGenerator.h
@ -3,7 +3,6 @@

 #include "Luau/Ast.h"
 #include "Luau/Constraint.h"
-#include "Luau/ConstraintSet.h"
 #include "Luau/ControlFlow.h"
 #include "Luau/DataFlowGraph.h"
 #include "Luau/EqSatSimplification.h"
@ -12,14 +11,15 @@
 #include "Luau/ModuleResolver.h"
 #include "Luau/Normalize.h"
 #include "Luau/NotNull.h"
-#include "Luau/Polarity.h"
 #include "Luau/Refinement.h"
 #include "Luau/Symbol.h"
 #include "Luau/TypeFwd.h"
 #include "Luau/TypeUtils.h"
+#include "Luau/Variant.h"

 #include <memory>
 #include <vector>
+#include <unordered_map>

 namespace Luau
 {
@ -92,11 +92,9 @@ struct ConstraintGenerator
    // Constraints that go straight to the solver.
    std::vector<ConstraintPtr> constraints;

-    // The set of all free types introduced during constraint generation.
-    DenseHashSet<TypeId> freeTypes{nullptr};
-
-    // Map a function's signature scope back to its signature type.
-    DenseHashMap<Scope*, TypeId> scopeToFunction{nullptr};
+    // Constraints that do not go to the solver right away.  Other constraints
+    // will enqueue them during solving.
+    std::vector<ConstraintPtr> unqueuedConstraints;

    // The private scope of type aliases for which the type parameters belong to.
    DenseHashMap<const AstStatTypeAlias*, ScopePtr> astTypeAliasDefiningScopes{nullptr};
@ -116,23 +114,18 @@ struct ConstraintGenerator

    // Needed to register all available type functions for execution at later stages.
    NotNull<TypeFunctionRuntime> typeFunctionRuntime;
-    DenseHashMap<const AstStatTypeFunction*, ScopePtr> astTypeFunctionEnvironmentScopes{nullptr};
-
    // Needed to resolve modules to make 'require' import types properly.
    NotNull<ModuleResolver> moduleResolver;
    // Occasionally constraint generation needs to produce an ICE.
    const NotNull<InternalErrorReporter> ice;

    ScopePtr globalScope;
-    ScopePtr typeFunctionScope;

    std::function<void(const ModuleName&, const ScopePtr&)> prepareModuleScope;
    std::vector<RequireCycle> requireCycles;

    DenseHashMap<TypeId, TypeIds> localTypes{nullptr};

-    DenseHashMap<AstExpr*, Inference> inferredExprCache{nullptr};
-
    DcrLogger* logger;

    ConstraintGenerator(
@ -144,16 +137,12 @@ struct ConstraintGenerator
        NotNull<BuiltinTypes> builtinTypes,
        NotNull<InternalErrorReporter> ice,
        const ScopePtr& globalScope,
-        const ScopePtr& typeFunctionScope,
        std::function<void(const ModuleName&, const ScopePtr&)> prepareModuleScope,
        DcrLogger* logger,
        NotNull<DataFlowGraph> dfg,
        std::vector<RequireCycle> requireCycles
    );

-    ConstraintSet run(AstStatBlock* block);
-    ConstraintSet runOnFragment(const ScopePtr& resumeScope, AstStatBlock* block);
-
    /**
     * The entry point to the ConstraintGenerator. This will construct a set
     * of scopes, constraints, and free types that can be solved later.
@ -164,26 +153,19 @@ struct ConstraintGenerator
    void visitFragmentRoot(const ScopePtr& resumeScope, AstStatBlock* block);

 private:
-    struct InteriorFreeTypes
-    {
-        std::vector<TypeId> types;
-        std::vector<TypePackId> typePacks;
-    };
-
-    std::vector<std::vector<TypeId>> DEPRECATED_interiorTypes;
-    std::vector<InteriorFreeTypes> interiorFreeTypes;
+    std::vector<std::vector<TypeId>> interiorTypes;

    /**
     * Fabricates a new free type belonging to a given scope.
     * @param scope the scope the free type belongs to.
     */
-    TypeId freshType(const ScopePtr& scope, Polarity polarity = Polarity::Unknown);
+    TypeId freshType(const ScopePtr& scope);

    /**
     * Fabricates a new free type pack belonging to a given scope.
     * @param scope the scope the free type pack belongs to.
     */
-    TypePackId freshTypePack(const ScopePtr& scope, Polarity polarity = Polarity::Unknown);
+    TypePackId freshTypePack(const ScopePtr& scope);

    /**
     * Allocate a new TypePack with the given head and tail.
@ -272,7 +254,7 @@ private:
    ControlFlow visit(const ScopePtr& scope, AstStatTypeAlias* alias);
    ControlFlow visit(const ScopePtr& scope, AstStatTypeFunction* function);
    ControlFlow visit(const ScopePtr& scope, AstStatDeclareGlobal* declareGlobal);
-    ControlFlow visit(const ScopePtr& scope, AstStatDeclareExternType* declareExternType);
+    ControlFlow visit(const ScopePtr& scope, AstStatDeclareClass* declareClass);
    ControlFlow visit(const ScopePtr& scope, AstStatDeclareFunction* declareFunction);
    ControlFlow visit(const ScopePtr& scope, AstStatError* error);

@ -304,7 +286,7 @@ private:
    );

    Inference check(const ScopePtr& scope, AstExprConstantString* string, std::optional<TypeId> expectedType, bool forceSingleton);
-    Inference check(const ScopePtr& scope, AstExprConstantBool* boolExpr, std::optional<TypeId> expectedType, bool forceSingleton);
+    Inference check(const ScopePtr& scope, AstExprConstantBool* bool_, std::optional<TypeId> expectedType, bool forceSingleton);
    Inference check(const ScopePtr& scope, AstExprLocal* local);
    Inference check(const ScopePtr& scope, AstExprGlobal* global);
    Inference checkIndexName(const ScopePtr& scope, const RefinementKey* key, AstExpr* indexee, const std::string& index, Location indexLocation);
@ -380,11 +362,6 @@ private:
     **/
    TypeId resolveType(const ScopePtr& scope, AstType* ty, bool inTypeArguments, bool replaceErrorWithFresh = false);

-    // resolveType() is recursive, but we only want to invoke
-    // inferGenericPolarities() once at the very end.  We thus isolate the
-    // recursive part of the algorithm to this internal helper.
-    TypeId resolveType_(const ScopePtr& scope, AstType* ty, bool inTypeArguments, bool replaceErrorWithFresh = false);
-
    /**
     * Resolves a type pack from its AST annotation.
     * @param scope the scope that the type annotation appears within.
@ -394,9 +371,6 @@ private:
     **/
    TypePackId resolveTypePack(const ScopePtr& scope, AstTypePack* tp, bool inTypeArguments, bool replaceErrorWithFresh = false);

-    // Inner hepler for resolveTypePack
-    TypePackId resolveTypePack_(const ScopePtr& scope, AstTypePack* tp, bool inTypeArguments, bool replaceErrorWithFresh = false);
-
    /**
     * Resolves a type pack from its AST annotation.
     * @param scope the scope that the type annotation appears within.
@ -418,7 +392,7 @@ private:
     **/
    std::vector<std::pair<Name, GenericTypeDefinition>> createGenerics(
        const ScopePtr& scope,
-        AstArray<AstGenericType*> generics,
+        AstArray<AstGenericType> generics,
        bool useCache = false,
        bool addTypes = true
    );
@ -435,7 +409,7 @@ private:
     **/
    std::vector<std::pair<Name, GenericTypePackDefinition>> createGenericPacks(
        const ScopePtr& scope,
-        AstArray<AstGenericTypePack*> generics,
+        AstArray<AstGenericTypePack> packs,
        bool useCache = false,
        bool addTypes = true
    );
@ -484,4 +458,9 @@ private:
    TypeId simplifyUnion(const ScopePtr& scope, Location location, TypeId left, TypeId right);
 };

+/** Borrow a vector of pointers from a vector of owning pointers to constraints.
+ */
+std::vector<NotNull<Constraint>> borrowConstraints(const std::vector<ConstraintPtr>& constraints);
+
+
 } // namespace Luau
--- a/Analysis/include/Luau/ConstraintSet.h
+++ b/Analysis/include/Luau/ConstraintSet.h
@ -1,32 +0,0 @@
-// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
-
-#pragma once
-
-#include "Luau/Constraint.h"
-#include "Luau/DenseHash.h"
-#include "Luau/Error.h"
-
-#include <vector>
-
-namespace Luau
-{
-
-struct ConstraintSet
-{
-    NotNull<Scope> rootScope;
-
-    std::vector<ConstraintPtr> constraints;
-
-    // The set of all free types created during constraint generation
-    DenseHashSet<TypeId> freeTypes{nullptr};
-
-    // Map a function's signature scope back to its signature type.   Once we've
-    // dispatched all of the constraints pertaining to a particular free type,
-    // we use this mapping to generalize that free type.
-    DenseHashMap<Scope*, TypeId> scopeToFunction{nullptr};
-
-    // It is pretty uncommon for constraint generation to itself produce errors, but it can happen.
-    std::vector<TypeError> errors;
-};
-
-}
--- a/Analysis/include/Luau/ConstraintSolver.h
+++ b/Analysis/include/Luau/ConstraintSolver.h
@ -3,7 +3,6 @@
 #pragma once

 #include "Luau/Constraint.h"
-#include "Luau/ConstraintSet.h"
 #include "Luau/DataFlowGraph.h"
 #include "Luau/DenseHash.h"
 #include "Luau/EqSatSimplification.h"
@ -88,9 +87,7 @@ struct ConstraintSolver
    NotNull<Simplifier> simplifier;
    NotNull<TypeFunctionRuntime> typeFunctionRuntime;
    // The entire set of constraints that the solver is trying to resolve.
-    ConstraintSet constraintSet;
    std::vector<NotNull<Constraint>> constraints;
-    NotNull<DenseHashMap<Scope*, TypeId>> scopeToFunction;
    NotNull<Scope> rootScope;
    ModuleName currentModuleName;

@ -121,9 +118,6 @@ struct ConstraintSolver
    // A mapping from free types to the number of unresolved constraints that mention them.
    DenseHashMap<TypeId, size_t> unresolvedConstraints{{}};

-    std::unordered_map<NotNull<const Constraint>, DenseHashSet<TypeId>> maybeMutatedFreeTypes;
-    std::unordered_map<TypeId, DenseHashSet<const Constraint*>> mutatedFreeTypeToConstraint;
-
    // Irreducible/uninhabited type functions or type pack functions.
    DenseHashSet<const void*> uninhabitedTypeFunctions{{}};

@ -142,26 +136,12 @@ struct ConstraintSolver

    DenseHashMap<TypeId, const Constraint*> typeFunctionsToFinalize{nullptr};

-    explicit ConstraintSolver(
-        NotNull<Normalizer> normalizer,
-        NotNull<Simplifier> simplifier,
-        NotNull<TypeFunctionRuntime> typeFunctionRuntime,
-        ModuleName moduleName,
-        NotNull<ModuleResolver> moduleResolver,
-        std::vector<RequireCycle> requireCycles,
-        DcrLogger* logger,
-        NotNull<const DataFlowGraph> dfg,
-        TypeCheckLimits limits,
-        ConstraintSet constraintSet
-    );
-
    explicit ConstraintSolver(
        NotNull<Normalizer> normalizer,
        NotNull<Simplifier> simplifier,
        NotNull<TypeFunctionRuntime> typeFunctionRuntime,
        NotNull<Scope> rootScope,
        std::vector<NotNull<Constraint>> constraints,
-        NotNull<DenseHashMap<Scope*, TypeId>> scopeToFunction,
        ModuleName moduleName,
        NotNull<ModuleResolver> moduleResolver,
        std::vector<RequireCycle> requireCycles,
@ -189,11 +169,6 @@ struct ConstraintSolver
    bool isDone() const;

 private:
-    /// A helper that does most of the setup work that is shared between the two constructors.
-    void initFreeTypeTracking();
-
-    void generalizeOneType(TypeId ty);
-
    /**
     * Bind a type variable to another type.
     *
@ -226,7 +201,6 @@ public:
    bool tryDispatch(const NameConstraint& c, NotNull<const Constraint> constraint);
    bool tryDispatch(const TypeAliasExpansionConstraint& c, NotNull<const Constraint> constraint);
    bool tryDispatch(const FunctionCallConstraint& c, NotNull<const Constraint> constraint);
-    bool tryDispatch(const TableCheckConstraint& c, NotNull<const Constraint> constraint);
    bool tryDispatch(const FunctionCheckConstraint& c, NotNull<const Constraint> constraint);
    bool tryDispatch(const PrimitiveTypeConstraint& c, NotNull<const Constraint> constraint);
    bool tryDispatch(const HasPropConstraint& c, NotNull<const Constraint> constraint);
@ -383,7 +357,7 @@ public:
     * @returns a non-free type that generalizes the argument, or `std::nullopt` if one
     * does not exist
     */
-    std::optional<TypeId> generalizeFreeType(NotNull<Scope> scope, TypeId type);
+    std::optional<TypeId> generalizeFreeType(NotNull<Scope> scope, TypeId type, bool avoidSealingTables = false);

    /**
     * Checks the existing set of constraints to see if there exist any that contain
@ -447,13 +421,12 @@ public:

    ToStringOptions opts;

-    void fillInDiscriminantTypes(NotNull<const Constraint> constraint, const std::vector<std::optional<TypeId>>& discriminantTypes);
+    void fillInDiscriminantTypes(
+        NotNull<const Constraint> constraint,
+        const std::vector<std::optional<TypeId>>& discriminantTypes
+    );
 };

-/** Borrow a vector of pointers from a vector of owning pointers to constraints.
- */
-std::vector<NotNull<Constraint>> borrowConstraints(const std::vector<ConstraintPtr>& constraints);
-
 void dump(NotNull<Scope> rootScope, struct ToStringOptions& opts);

 } // namespace Luau
--- a/Analysis/include/Luau/DataFlowGraph.h
+++ b/Analysis/include/Luau/DataFlowGraph.h
@ -38,6 +38,8 @@ struct DataFlowGraph
    DefId getDef(const AstExpr* expr) const;
    // Look up the definition optionally, knowing it may not be present.
    std::optional<DefId> getDefOptional(const AstExpr* expr) const;
+    // Look up for the rvalue def for a compound assignment.
+    std::optional<DefId> getRValueDefForCompoundAssign(const AstExpr* expr) const;

    DefId getDef(const AstLocal* local) const;

@ -64,6 +66,10 @@ private:
    // All keys in this maps are really only statements that ambiently declares a symbol.
    DenseHashMap<const AstStat*, const Def*> declaredDefs{nullptr};

+    // Compound assignments are in a weird situation where the local being assigned to is also being used at its
+    // previous type implicitly in an rvalue position. This map provides the previous binding.
+    DenseHashMap<const AstExpr*, const Def*> compoundAssignDefs{nullptr};
+
    DenseHashMap<const AstExpr*, const RefinementKey*> astRefinementKeys{nullptr};
    friend struct DataFlowGraphBuilder;
 };
@ -129,8 +135,8 @@ private:

    /// A stack of scopes used by the visitor to see where we are.
    ScopeStack scopeStack;
-    NotNull<DfgScope> currentScope();
-    DfgScope* currentScope_DEPRECATED();
+
+    DfgScope* currentScope();

    struct FunctionCapture
    {
@ -148,8 +154,8 @@ private:
    void joinBindings(DfgScope* p, const DfgScope& a, const DfgScope& b);
    void joinProps(DfgScope* p, const DfgScope& a, const DfgScope& b);

-    DefId lookup(Symbol symbol, Location location);
-    DefId lookup(DefId def, const std::string& key, Location location);
+    DefId lookup(Symbol symbol);
+    DefId lookup(DefId def, const std::string& key);

    ControlFlow visit(AstStatBlock* b);
    ControlFlow visitBlockWithoutChildScope(AstStatBlock* b);
@ -173,7 +179,7 @@ private:
    ControlFlow visit(AstStatTypeFunction* f);
    ControlFlow visit(AstStatDeclareGlobal* d);
    ControlFlow visit(AstStatDeclareFunction* d);
-    ControlFlow visit(AstStatDeclareExternType* d);
+    ControlFlow visit(AstStatDeclareClass* d);
    ControlFlow visit(AstStatError* error);

    DataFlowResult visitExpr(AstExpr* e);
@ -215,8 +221,8 @@ private:

    void visitTypeList(AstTypeList l);

-    void visitGenerics(AstArray<AstGenericType*> g);
-    void visitGenericPacks(AstArray<AstGenericTypePack*> g);
+    void visitGenerics(AstArray<AstGenericType> g);
+    void visitGenericPacks(AstArray<AstGenericTypePack> g);
 };

 } // namespace Luau
--- a/Analysis/include/Luau/Def.h
+++ b/Analysis/include/Luau/Def.h
@ -4,8 +4,7 @@
 #include "Luau/NotNull.h"
 #include "Luau/TypedAllocator.h"
 #include "Luau/Variant.h"
-#include "Luau/Location.h"
-#include "Luau/Symbol.h"
+
 #include <string>
 #include <optional>

@ -14,7 +13,6 @@ namespace Luau

 struct Def;
 using DefId = NotNull<const Def>;
-struct AstLocal;

 /**
 * A cell is a "single-object" value.
@ -66,8 +64,6 @@ struct Def
    using V = Variant<struct Cell, struct Phi>;

    V v;
-    Symbol name;
-    Location location;
 };

 template<typename T>
@ -83,7 +79,7 @@ struct DefArena
 {
    TypedAllocator<Def> allocator;

-    DefId freshCell(Symbol sym, Location location, bool subscripted = false);
+    DefId freshCell(bool subscripted = false);
    DefId phi(DefId a, DefId b);
    DefId phi(const std::vector<DefId>& defs);
 };
--- a/Analysis/include/Luau/EqSatSimplificationImpl.h
+++ b/Analysis/include/Luau/EqSatSimplificationImpl.h
@ -105,7 +105,7 @@ private:
    std::vector<Id> storage;
 };

-template<typename L>
+template <typename L>
 using Node = EqSat::Node<L>;

 using EType = EqSat::Language<
@ -149,7 +149,7 @@ using EType = EqSat::Language<
 struct StringCache
 {
    Allocator allocator;
-    DenseHashMap<std::string_view, StringId> strings{{}};
+    DenseHashMap<size_t, StringId> strings{{}};
    std::vector<std::string_view> views;

    StringId add(std::string_view s);
--- a/Analysis/include/Luau/Error.h
+++ b/Analysis/include/Luau/Error.h
@ -332,11 +332,11 @@ struct TypePackMismatch
    bool operator==(const TypePackMismatch& rhs) const;
 };

-struct DynamicPropertyLookupOnExternTypesUnsafe
+struct DynamicPropertyLookupOnClassesUnsafe
 {
    TypeId ty;

-    bool operator==(const DynamicPropertyLookupOnExternTypesUnsafe& rhs) const;
+    bool operator==(const DynamicPropertyLookupOnClassesUnsafe& rhs) const;
 };

 struct UninhabitedTypeFunction
@ -455,13 +455,6 @@ struct UserDefinedTypeFunctionError
    bool operator==(const UserDefinedTypeFunctionError& rhs) const;
 };

-struct ReservedIdentifier
-{
-    std::string name;
-
-    bool operator==(const ReservedIdentifier& rhs) const;
-};
-
 using TypeErrorData = Variant<
    TypeMismatch,
    UnknownSymbol,
@ -499,7 +492,7 @@ using TypeErrorData = Variant<
    TypesAreUnrelated,
    NormalizationTooComplex,
    TypePackMismatch,
-    DynamicPropertyLookupOnExternTypesUnsafe,
+    DynamicPropertyLookupOnClassesUnsafe,
    UninhabitedTypeFunction,
    UninhabitedTypePackFunction,
    WhereClauseNeeded,
@ -511,8 +504,7 @@ using TypeErrorData = Variant<
    UnexpectedTypeInSubtyping,
    UnexpectedTypePackInSubtyping,
    ExplicitFunctionAnnotationRecommended,
-    UserDefinedTypeFunctionError,
-    ReservedIdentifier>;
+    UserDefinedTypeFunctionError>;

 struct TypeErrorSummary
 {
--- a/Analysis/include/Luau/FileResolver.h
+++ b/Analysis/include/Luau/FileResolver.h
@ -1,9 +1,8 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
 #pragma once

-#include <memory>
-#include <optional>
 #include <string>
+#include <optional>
 #include <vector>

 namespace Luau
@ -20,7 +19,7 @@ struct SourceCode
        None,
        Module,
        Script,
-        Local_DEPRECATED
+        Local
    };

    std::string source;
@ -33,71 +32,15 @@ struct ModuleInfo
    bool optional = false;
 };

-struct RequireAlias
-{
-    std::string alias; // Unprefixed alias name (no leading `@`).
-    std::vector<std::string> tags = {};
-};
-
-struct RequireNode
-{
-    virtual ~RequireNode() {}
-
-    // Get the path component representing this node.
-    virtual std::string getPathComponent() const = 0;
-
-    // Get the displayed user-facing label for this node, defaults to getPathComponent()
-    virtual std::string getLabel() const
-    {
-        return getPathComponent();
-    }
-
-    // Get tags to attach to this node's RequireSuggestion (defaults to none).
-    virtual std::vector<std::string> getTags() const
-    {
-        return {};
-    }
-
-    // TODO: resolvePathToNode() can ultimately be replaced with a call into
-    // require-by-string's path resolution algorithm. This will first require
-    // generalizing that algorithm to work with a virtual file system.
-    virtual std::unique_ptr<RequireNode> resolvePathToNode(const std::string& path) const = 0;
-
-    // Get children of this node, if any (if this node represents a directory).
-    virtual std::vector<std::unique_ptr<RequireNode>> getChildren() const = 0;
-
-    // A list of the aliases available to this node.
-    virtual std::vector<RequireAlias> getAvailableAliases() const = 0;
-};
-
 struct RequireSuggestion
 {
    std::string label;
    std::string fullPath;
-    std::vector<std::string> tags;
 };
 using RequireSuggestions = std::vector<RequireSuggestion>;

-struct RequireSuggester
-{
-    virtual ~RequireSuggester() {}
-    std::optional<RequireSuggestions> getRequireSuggestions(const ModuleName& requirer, const std::optional<std::string>& pathString) const;
-
-protected:
-    virtual std::unique_ptr<RequireNode> getNode(const ModuleName& name) const = 0;
-
-private:
-    std::optional<RequireSuggestions> getRequireSuggestionsImpl(const ModuleName& requirer, const std::optional<std::string>& path) const;
-};
-
 struct FileResolver
 {
-    FileResolver() = default;
-    FileResolver(std::shared_ptr<RequireSuggester> requireSuggester)
-        : requireSuggester(std::move(requireSuggester))
-    {
-    }
-
    virtual ~FileResolver() {}

    virtual std::optional<SourceCode> readSource(const ModuleName& name) = 0;
@ -117,9 +60,10 @@ struct FileResolver
        return std::nullopt;
    }

-    std::optional<RequireSuggestions> getRequireSuggestions(const ModuleName& requirer, const std::optional<std::string>& pathString) const;
-
-    std::shared_ptr<RequireSuggester> requireSuggester;
+    virtual std::optional<RequireSuggestions> getRequireSuggestions(const ModuleName& requirer, const std::optional<std::string>& pathString) const
+    {
+        return std::nullopt;
+    }
 };

 struct NullFileResolver : FileResolver
--- a/Analysis/include/Luau/FragmentAutocomplete.h
+++ b/Analysis/include/Luau/FragmentAutocomplete.h
@ -15,28 +15,6 @@ namespace Luau
 {
 struct FrontendOptions;

-enum class FragmentAutocompleteWaypoint
-{
-    ParseFragmentEnd,
-    CloneModuleStart,
-    CloneModuleEnd,
-    DfgBuildEnd,
-    CloneAndSquashScopeStart,
-    CloneAndSquashScopeEnd,
-    ConstraintSolverStart,
-    ConstraintSolverEnd,
-    TypecheckFragmentEnd,
-    AutocompleteEnd,
-    COUNT,
-};
-
-class IFragmentAutocompleteReporter
-{
-public:
-    virtual void reportWaypoint(FragmentAutocompleteWaypoint) = 0;
-    virtual void reportFragmentString(std::string_view) = 0;
-};
-
 enum class FragmentTypeCheckStatus
 {
    SkipAutocomplete,
@ -49,8 +27,6 @@ struct FragmentAutocompleteAncestryResult
    std::vector<AstLocal*> localStack;
    std::vector<AstNode*> ancestry;
    AstStat* nearestStatement = nullptr;
-    AstStatBlock* parentBlock = nullptr;
-    Location fragmentSelectionRegion;
 };

 struct FragmentParseResult
@ -61,7 +37,6 @@ struct FragmentParseResult
    AstStat* nearestStatement = nullptr;
    std::vector<Comment> commentLocations;
    std::unique_ptr<Allocator> alloc = std::make_unique<Allocator>();
-    Position scopePos{0, 0};
 };

 struct FragmentTypeCheckResult
@ -75,34 +50,14 @@ struct FragmentAutocompleteResult
 {
    ModulePtr incrementalModule;
    Scope* freshScope;
-    TypeArena arenaForAutocomplete_DEPRECATED;
+    TypeArena arenaForAutocomplete;
    AutocompleteResult acResults;
 };

-struct FragmentRegion
-{
-    Location fragmentLocation;
-    AstStat* nearestStatement = nullptr; // used for tests
-    AstStatBlock* parentBlock = nullptr; // used for scope detection
-};
-
-std::optional<Position> blockDiffStart(AstStatBlock* blockOld, AstStatBlock* blockNew, AstStat* nearestStatementNewAst);
-FragmentRegion getFragmentRegion(AstStatBlock* root, const Position& cursorPosition);
-FragmentAutocompleteAncestryResult findAncestryForFragmentParse(AstStatBlock* stale, const Position& cursorPos, AstStatBlock* lastGoodParse);
-FragmentAutocompleteAncestryResult findAncestryForFragmentParse_DEPRECATED(AstStatBlock* root, const Position& cursorPos);
-
-std::optional<FragmentParseResult> parseFragment_DEPRECATED(
-    AstStatBlock* root,
-    AstNameTable* names,
-    std::string_view src,
-    const Position& cursorPos,
-    std::optional<Position> fragmentEndPosition
-);
+FragmentAutocompleteAncestryResult findAncestryForFragmentParse(AstStatBlock* root, const Position& cursorPos);

 std::optional<FragmentParseResult> parseFragment(
-    AstStatBlock* stale,
-    AstStatBlock* mostRecentParse,
-    AstNameTable* names,
+    const SourceModule& srcModule,
    std::string_view src,
    const Position& cursorPos,
    std::optional<Position> fragmentEndPosition
@ -114,9 +69,7 @@ std::pair<FragmentTypeCheckStatus, FragmentTypeCheckResult> typecheckFragment(
    const Position& cursorPos,
    std::optional<FrontendOptions> opts,
    std::string_view src,
-    std::optional<Position> fragmentEndPosition,
-    AstStatBlock* recentParse = nullptr,
-    IFragmentAutocompleteReporter* reporter = nullptr
+    std::optional<Position> fragmentEndPosition
 );

 FragmentAutocompleteResult fragmentAutocomplete(
@ -126,71 +79,8 @@ FragmentAutocompleteResult fragmentAutocomplete(
    Position cursorPosition,
    std::optional<FrontendOptions> opts,
    StringCompletionCallback callback,
-    std::optional<Position> fragmentEndPosition = std::nullopt,
-    AstStatBlock* recentParse = nullptr,
-    IFragmentAutocompleteReporter* reporter = nullptr
+    std::optional<Position> fragmentEndPosition = std::nullopt
 );

-enum class FragmentAutocompleteStatus
-{
-    Success,
-    FragmentTypeCheckFail,
-    InternalIce
-};
-
-struct FragmentAutocompleteStatusResult
-{
-    FragmentAutocompleteStatus status;
-    std::optional<FragmentAutocompleteResult> result;
-};
-
-struct FragmentContext
-{
-    std::string_view newSrc;
-    const ParseResult& freshParse;
-    std::optional<FrontendOptions> opts;
-    std::optional<Position> DEPRECATED_fragmentEndPosition;
-    IFragmentAutocompleteReporter* reporter = nullptr;
-};
-
-/**
- * @brief Attempts to compute autocomplete suggestions from the fragment context.
- *
- * This function computes autocomplete suggestions using outdated frontend typechecking data
- * by patching the fragment context of the new script source content.
- *
- * @param frontend The Luau Frontend data structure, which may contain outdated typechecking data.
- *
- * @param moduleName The name of the target module, specifying which script the caller wants to request autocomplete for.
- *
- * @param cursorPosition The position in the script where the caller wants to trigger autocomplete.
- *
- * @param context The fragment context that this API will use to patch the outdated typechecking data.
- *
- * @param stringCompletionCB A callback function that provides autocomplete suggestions for string contexts.
- *
- * @return
- * The status indicating whether `fragmentAutocomplete` ran successfully or failed, along with the reason for failure.
- * Also includes autocomplete suggestions if the status is successful.
- *
- * @usage
- * FragmentAutocompleteStatusResult acStatusResult;
- * if (shouldFragmentAC)
- *     acStatusResult = Luau::tryFragmentAutocomplete(...);
- *
- * if (acStatusResult.status != Successful)
- * {
- *     frontend.check(moduleName, options);
- *     acStatusResult.acResult = Luau::autocomplete(...);
- * }
- * return convertResultWithContext(acStatusResult.acResult);
- */
-FragmentAutocompleteStatusResult tryFragmentAutocomplete(
-    Frontend& frontend,
-    const ModuleName& moduleName,
-    Position cursorPosition,
-    FragmentContext context,
-    StringCompletionCallback stringCompletionCB
-);

 } // namespace Luau
--- a/Analysis/include/Luau/Frontend.h
+++ b/Analysis/include/Luau/Frontend.h
@ -7,9 +7,9 @@
 #include "Luau/ModuleResolver.h"
 #include "Luau/RequireTracer.h"
 #include "Luau/Scope.h"
-#include "Luau/Set.h"
 #include "Luau/TypeCheckLimits.h"
 #include "Luau/Variant.h"
+#include "Luau/AnyTypeSummary.h"

 #include <mutex>
 #include <string>
@ -31,8 +31,8 @@ struct ModuleResolver;
 struct ParseResult;
 struct HotComment;
 struct BuildQueueItem;
-struct BuildQueueWorkState;
 struct FrontendCancellationToken;
+struct AnyTypeSummary;

 struct LoadDefinitionFileResult
 {
@ -56,32 +56,13 @@ struct SourceNode
        return forAutocomplete ? dirtyModuleForAutocomplete : dirtyModule;
    }

-    bool hasInvalidModuleDependency(bool forAutocomplete) const
-    {
-        return forAutocomplete ? invalidModuleDependencyForAutocomplete : invalidModuleDependency;
-    }
-
-    void setInvalidModuleDependency(bool value, bool forAutocomplete)
-    {
-        if (forAutocomplete)
-            invalidModuleDependencyForAutocomplete = value;
-        else
-            invalidModuleDependency = value;
-    }
-
    ModuleName name;
    std::string humanReadableName;
    DenseHashSet<ModuleName> requireSet{{}};
    std::vector<std::pair<ModuleName, Location>> requireLocations;
-    Set<ModuleName> dependents{{}};
-
    bool dirtySourceModule = true;
    bool dirtyModule = true;
    bool dirtyModuleForAutocomplete = true;
-
-    bool invalidModuleDependency = true;
-    bool invalidModuleDependencyForAutocomplete = true;
-
    double autocompleteLimitsMult = 1.0;
 };

@ -136,7 +117,7 @@ struct FrontendModuleResolver : ModuleResolver
    std::optional<ModuleInfo> resolveModuleInfo(const ModuleName& currentModuleName, const AstExpr& pathExpr) override;
    std::string getHumanReadableModuleName(const ModuleName& moduleName) const override;

-    bool setModule(const ModuleName& moduleName, ModulePtr module);
+    void setModule(const ModuleName& moduleName, ModulePtr module);
    void clearModules();

 private:
@ -170,13 +151,9 @@ struct Frontend
    // Parse and typecheck module graph
    CheckResult check(const ModuleName& name, std::optional<FrontendOptions> optionOverride = {}); // new shininess

-    bool allModuleDependenciesValid(const ModuleName& name, bool forAutocomplete = false) const;
-
    bool isDirty(const ModuleName& name, bool forAutocomplete = false) const;
    void markDirty(const ModuleName& name, std::vector<ModuleName>* markedDirty = nullptr);

-    void traverseDependents(const ModuleName& name, std::function<bool(SourceNode&)> processSubtree);
-
    /** Borrow a pointer into the SourceModule cache.
     *
     * Returns nullptr if we don't have it.  This could mean that the script
@ -250,9 +227,6 @@ private:
    void checkBuildQueueItem(BuildQueueItem& item);
    void checkBuildQueueItems(std::vector<BuildQueueItem>& items);
    void recordItemResult(const BuildQueueItem& item);
-    void performQueueItemTask(std::shared_ptr<BuildQueueWorkState> state, size_t itemPos);
-    void sendQueueItemTask(std::shared_ptr<BuildQueueWorkState> state, size_t itemPos);
-    void sendQueueCycleItemTask(std::shared_ptr<BuildQueueWorkState> state);

    static LintResult classifyLints(const std::vector<LintWarning>& warnings, const Config& config);

@ -298,7 +272,6 @@ ModulePtr check(
    NotNull<ModuleResolver> moduleResolver,
    NotNull<FileResolver> fileResolver,
    const ScopePtr& globalScope,
-    const ScopePtr& typeFunctionScope,
    std::function<void(const ModuleName&, const ScopePtr&)> prepareModuleScope,
    FrontendOptions options,
    TypeCheckLimits limits
@ -313,7 +286,6 @@ ModulePtr check(
    NotNull<ModuleResolver> moduleResolver,
    NotNull<FileResolver> fileResolver,
    const ScopePtr& globalScope,
-    const ScopePtr& typeFunctionScope,
    std::function<void(const ModuleName&, const ScopePtr&)> prepareModuleScope,
    FrontendOptions options,
    TypeCheckLimits limits,
--- a/Analysis/include/Luau/Generalization.h
+++ b/Analysis/include/Luau/Generalization.h
@ -8,75 +8,12 @@
 namespace Luau
 {

-template<typename TID>
-struct GeneralizationParams
-{
-    bool foundOutsideFunctions = false;
-    size_t useCount = 0;
-    Polarity polarity = Polarity::None;
-};
-
-template<typename TID>
-struct GeneralizationResult
-{
-    std::optional<TID> result;
-
-    // True if the provided type was replaced with a generic.
-    bool wasReplacedByGeneric = false;
-
-    bool resourceLimitsExceeded = false;
-
-    explicit operator bool() const
-    {
-        return bool(result);
-    }
-};
-
-// Replace a single free type by its bounds according to the polarity provided.
-GeneralizationResult<TypeId> generalizeType(
-    NotNull<TypeArena> arena,
-    NotNull<BuiltinTypes> builtinTypes,
-    NotNull<Scope> scope,
-    TypeId freeTy,
-    const GeneralizationParams<TypeId>& params
-);
-
-// Generalize one type pack
-GeneralizationResult<TypePackId> generalizeTypePack(
-    NotNull<TypeArena> arena,
-    NotNull<BuiltinTypes> builtinTypes,
-    NotNull<Scope> scope,
-    TypePackId tp,
-    const GeneralizationParams<TypePackId>& params
-);
-
-void sealTable(NotNull<Scope> scope, TypeId ty);
-
-/** Attempt to generalize a type.
- *
- * If generalizationTarget is set, then only that type will be replaced by its
- * bounds.  The way this is intended to be used is that ty is some function that
- * is not fully generalized, and generalizationTarget is a type within its
- * signature.  There should be no further constraints that could affect the
- * bounds of generalizationTarget.
- *
- * Returns nullopt if generalization failed due to resources limits.
- */
 std::optional<TypeId> generalize(
    NotNull<TypeArena> arena,
    NotNull<BuiltinTypes> builtinTypes,
    NotNull<Scope> scope,
-    NotNull<DenseHashSet<TypeId>> cachedTypes,
+    NotNull<DenseHashSet<TypeId>> bakedTypes,
    TypeId ty,
-    std::optional<TypeId> generalizationTarget = {}
+    /* avoid sealing tables*/ bool avoidSealingTables = false
 );
-
-void pruneUnnecessaryGenerics(
-    NotNull<TypeArena> arena,
-    NotNull<BuiltinTypes> builtinTypes,
-    NotNull<Scope> scope,
-    NotNull<DenseHashSet<TypeId>> cachedTypes,
-    TypeId ty
-);
-
-} // namespace Luau
+}
--- a/Analysis/include/Luau/GlobalTypes.h
+++ b/Analysis/include/Luau/GlobalTypes.h
@ -19,9 +19,7 @@ struct GlobalTypes

    TypeArena globalTypes;
    SourceModule globalNames; // names for symbols entered into globalScope
-
    ScopePtr globalScope;     // shared by all modules
-    ScopePtr globalTypeFunctionScope; // shared by all modules
 };

 } // namespace Luau
--- a/Analysis/include/Luau/InferPolarity.h
+++ b/Analysis/include/Luau/InferPolarity.h
@ -1,16 +0,0 @@
-// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
-#pragma once
-
-#include "Luau/NotNull.h"
-#include "Luau/TypeFwd.h"
-
-namespace Luau
-{
-
-struct Scope;
-struct TypeArena;
-
-void inferGenericPolarities(NotNull<TypeArena> arena, NotNull<Scope> scope, TypeId ty);
-void inferGenericPolarities(NotNull<TypeArena> arena, NotNull<Scope> scope, TypePackId tp);
-
-} // namespace Luau
--- a/Analysis/include/Luau/InsertionOrderedMap.h
+++ b/Analysis/include/Luau/InsertionOrderedMap.h
@ -67,19 +67,6 @@ public:
            return &pairs.at(it->second).second;
    }

-    V& operator[](const K& k)
-    {
-        auto it = indices.find(k);
-        if (it == indices.end())
-        {
-            pairs.push_back(std::make_pair(k, V()));
-            indices[k] = pairs.size() - 1;
-            return pairs.back().second;
-        }
-        else
-            return pairs.at(it->second).second;
-    }
-
    const_iterator begin() const
    {
        return pairs.begin();
--- a/Analysis/include/Luau/Instantiation.h
+++ b/Analysis/include/Luau/Instantiation.h
@ -133,9 +133,9 @@ struct GenericTypeFinder : TypeOnceVisitor
        return false;
    }

-    bool visit(TypeId ty, const Luau::ExternType&) override
+    bool visit(TypeId ty, const Luau::ClassType&) override
    {
-        // During function instantiation, extern types are not traversed even if they have generics
+        // During function instantiation, classes are not traversed even if they have generics
        return false;
    }
 };
--- a/Analysis/include/Luau/Module.h
+++ b/Analysis/include/Luau/Module.h
@ -8,6 +8,7 @@
 #include "Luau/ParseResult.h"
 #include "Luau/Scope.h"
 #include "Luau/TypeArena.h"
+#include "Luau/AnyTypeSummary.h"
 #include "Luau/DataFlowGraph.h"

 #include <memory>
@ -15,16 +16,13 @@
 #include <unordered_map>
 #include <optional>

+LUAU_FASTFLAG(LuauIncrementalAutocompleteCommentDetection)
+
 namespace Luau
 {

-using LogLuauProc = void (*)(std::string_view, std::string_view);
-extern LogLuauProc logLuau;
-
-void setLogLuau(LogLuauProc ll);
-void resetLogLuauProc();
-
 struct Module;
+struct AnyTypeSummary;

 using ScopePtr = std::shared_ptr<struct Scope>;
 using ModulePtr = std::shared_ptr<Module>;
@ -82,10 +80,13 @@ struct Module
    TypeArena interfaceTypes;
    TypeArena internalTypes;

+    // Summary of Ast Nodes that either contain
+    // user annotated anys or typechecker inferred anys
+    AnyTypeSummary ats{};
+
    // Scopes and AST types refer to parse data, so we need to keep that alive
    std::shared_ptr<Allocator> allocator;
    std::shared_ptr<AstNameTable> names;
-    AstStatBlock* root = nullptr;

    std::vector<std::pair<Location, ScopePtr>> scopes; // never empty

--- a/Analysis/include/Luau/NonStrictTypeChecker.h
+++ b/Analysis/include/Luau/NonStrictTypeChecker.h
@ -1,10 +1,9 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
 #pragma once

-#include "Luau/DataFlowGraph.h"
-#include "Luau/EqSatSimplification.h"
 #include "Luau/Module.h"
 #include "Luau/NotNull.h"
+#include "Luau/DataFlowGraph.h"

 namespace Luau
 {
--- a/Analysis/include/Luau/Normalize.h
+++ b/Analysis/include/Luau/Normalize.h
@ -181,7 +181,7 @@ struct NormalizedStringType

 bool isSubtype(const NormalizedStringType& subStr, const NormalizedStringType& superStr);

-struct NormalizedExternType
+struct NormalizedClassType
 {
    /** Has the following structure:
     *
@ -192,7 +192,7 @@ struct NormalizedExternType
     *
     * Each TypeId is a class type.
     */
-    std::unordered_map<TypeId, TypeIds> externTypes;
+    std::unordered_map<TypeId, TypeIds> classes;

    /**
     * In order to maintain a consistent insertion order, we use this vector to
@ -245,7 +245,7 @@ enum class NormalizationResult
 };

 // A normalized type is either any, unknown, or one of the form P | T | F | G where
-// * P is a union of primitive types (including singletons, extern types and the error type)
+// * P is a union of primitive types (including singletons, classes and the error type)
 // * T is a union of table types
 // * F is a union of an intersection of function types
 // * G is a union of generic/free/blocked types, intersected with a normalized type
@ -260,7 +260,7 @@ struct NormalizedType
    // This type is either never, boolean type, or a boolean singleton.
    TypeId booleans;

-    NormalizedExternType externTypes;
+    NormalizedClassType classes;

    // The error part of the type.
    // This type is either never or the error type.
@ -333,7 +333,7 @@ struct NormalizedType
    // Helpers that improve readability of the above (they just say if the component is present)
    bool hasTops() const;
    bool hasBooleans() const;
-    bool hasExternTypes() const;
+    bool hasClasses() const;
    bool hasErrors() const;
    bool hasNils() const;
    bool hasNumbers() const;
@ -391,10 +391,10 @@ public:
    void unionTysWithTy(TypeIds& here, TypeId there);
    TypeId unionOfTops(TypeId here, TypeId there);
    TypeId unionOfBools(TypeId here, TypeId there);
-    void unionExternTypesWithExternType(TypeIds& heres, TypeId there);
-    void unionExternTypes(TypeIds& heres, const TypeIds& theres);
-    void unionExternTypesWithExternType(NormalizedExternType& heres, TypeId there);
-    void unionExternTypes(NormalizedExternType& heres, const NormalizedExternType& theres);
+    void unionClassesWithClass(TypeIds& heres, TypeId there);
+    void unionClasses(TypeIds& heres, const TypeIds& theres);
+    void unionClassesWithClass(NormalizedClassType& heres, TypeId there);
+    void unionClasses(NormalizedClassType& heres, const NormalizedClassType& theres);
    void unionStrings(NormalizedStringType& here, const NormalizedStringType& there);
    std::optional<TypePackId> unionOfTypePacks(TypePackId here, TypePackId there);
    std::optional<TypeId> unionOfFunctions(TypeId here, TypeId there);
@ -423,8 +423,8 @@ public:
    // ------- Normalizing intersections
    TypeId intersectionOfTops(TypeId here, TypeId there);
    TypeId intersectionOfBools(TypeId here, TypeId there);
-    void intersectExternTypes(NormalizedExternType& heres, const NormalizedExternType& theres);
-    void intersectExternTypesWithExternType(NormalizedExternType& heres, TypeId there);
+    void intersectClasses(NormalizedClassType& heres, const NormalizedClassType& theres);
+    void intersectClassesWithClass(NormalizedClassType& heres, TypeId there);
    void intersectStrings(NormalizedStringType& here, const NormalizedStringType& there);
    std::optional<TypePackId> intersectionOfTypePacks(TypePackId here, TypePackId there);
    std::optional<TypeId> intersectionOfTables(TypeId here, TypeId there, SeenTablePropPairs& seenTablePropPairs, Set<TypeId>& seenSet);
--- a/Analysis/include/Luau/Polarity.h
+++ b/Analysis/include/Luau/Polarity.h
@ -1,68 +0,0 @@
-// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
-#pragma once
-
-#include <cstdint>
-
-namespace Luau
-{
-
-enum struct Polarity : uint8_t
-{
-    None = 0b000,
-    Positive = 0b001,
-    Negative = 0b010,
-    Mixed = 0b011,
-    Unknown = 0b100,
-};
-
-inline Polarity operator|(Polarity lhs, Polarity rhs)
-{
-    return Polarity(uint8_t(lhs) | uint8_t(rhs));
-}
-
-inline Polarity& operator|=(Polarity& lhs, Polarity rhs)
-{
-    lhs = lhs | rhs;
-    return lhs;
-}
-
-inline Polarity operator&(Polarity lhs, Polarity rhs)
-{
-    return Polarity(uint8_t(lhs) & uint8_t(rhs));
-}
-
-inline Polarity& operator&=(Polarity& lhs, Polarity rhs)
-{
-    lhs = lhs & rhs;
-    return lhs;
-}
-
-inline bool isPositive(Polarity p)
-{
-    return bool(p & Polarity::Positive);
-}
-
-inline bool isNegative(Polarity p)
-{
-    return bool(p & Polarity::Negative);
-}
-
-inline bool isKnown(Polarity p)
-{
-    return p != Polarity::Unknown;
-}
-
-inline Polarity invert(Polarity p)
-{
-    switch (p)
-    {
-    case Polarity::Positive:
-        return Polarity::Negative;
-    case Polarity::Negative:
-        return Polarity::Positive;
-    default:
-        return p;
-    }
-}
-
-} // namespace Luau
--- a/Analysis/include/Luau/Quantify.h
+++ b/Analysis/include/Luau/Quantify.h
@ -16,7 +16,7 @@ struct Scope;

 void quantify(TypeId ty, TypeLevel level);

-// TODO: This is eerily similar to the pattern that NormalizedExternType
+// TODO: This is eerily similar to the pattern that NormalizedClassType
 // implements. We could, and perhaps should, merge them together.
 template<typename K, typename V>
 struct OrderedMap
@ -31,4 +31,13 @@ struct OrderedMap
    }
 };

+struct QuantifierResult
+{
+    TypeId result;
+    OrderedMap<TypeId, TypeId> insertedGenerics;
+    OrderedMap<TypePackId, TypePackId> insertedGenericPacks;
+};
+
+std::optional<QuantifierResult> quantify(TypeArena* arena, TypeId ty, Scope* scope);
+
 } // namespace Luau
--- a/Analysis/include/Luau/Refinement.h
+++ b/Analysis/include/Luau/Refinement.h
@ -53,7 +53,6 @@ struct Proposition
 {
    const RefinementKey* key;
    TypeId discriminantTy;
-    bool implicitFromCall;
 };

 template<typename T>
@ -70,7 +69,6 @@ struct RefinementArena
    RefinementId disjunction(RefinementId lhs, RefinementId rhs);
    RefinementId equivalence(RefinementId lhs, RefinementId rhs);
    RefinementId proposition(const RefinementKey* key, TypeId discriminantTy);
-    RefinementId implicitProposition(const RefinementKey* key, TypeId discriminantTy);

 private:
    TypedAllocator<Refinement> allocator;
--- a/Analysis/include/Luau/RequireTracer.h
+++ b/Analysis/include/Luau/RequireTracer.h
@ -11,12 +11,14 @@
 namespace Luau
 {

-class AstNode;
+class AstStat;
+class AstExpr;
 class AstStatBlock;
+struct AstLocal;

 struct RequireTraceResult
 {
-    DenseHashMap<const AstNode*, ModuleInfo> exprs{nullptr};
+    DenseHashMap<const AstExpr*, ModuleInfo> exprs{nullptr};

    std::vector<std::pair<ModuleName, Location>> requireList;
 };
--- a/Analysis/include/Luau/Scope.h
+++ b/Analysis/include/Luau/Scope.h
@ -35,12 +35,12 @@ struct Scope
    explicit Scope(TypePackId returnType);                    // root scope
    explicit Scope(const ScopePtr& parent, int subLevel = 0); // child scope.  Parent must not be nullptr.

-    ScopePtr parent; // null for the root
+    const ScopePtr parent; // null for the root

    // All the children of this scope.
    std::vector<NotNull<Scope>> children;
    std::unordered_map<Symbol, Binding> bindings;
-    TypePackId returnType = nullptr;
+    TypePackId returnType;
    std::optional<TypePackId> varargPack;

    TypeLevel level;
@ -59,8 +59,6 @@ struct Scope

    std::optional<TypeId> lookup(Symbol sym) const;
    std::optional<TypeId> lookupUnrefinedType(DefId def) const;
-
-    std::optional<TypeId> lookupRValueRefinementType(DefId def) const;
    std::optional<TypeId> lookup(DefId def) const;
    std::optional<std::pair<TypeId, Scope*>> lookupEx(DefId def);
    std::optional<std::pair<Binding*, Scope*>> lookupEx(Symbol sym);
@ -73,7 +71,6 @@ struct Scope

    // WARNING: This function linearly scans for a string key of equal value!  It is thus O(n**2)
    std::optional<Binding> linearSearchForBinding(const std::string& name, bool traverseScopeChain = true) const;
-    std::optional<std::pair<Symbol, Binding>> linearSearchForBindingPair(const std::string& name, bool traverseScopeChain) const;

    RefinementMap refinements;

@ -100,7 +97,6 @@ struct Scope
    std::unordered_map<Name, TypePackId> typeAliasTypePackParameters;

    std::optional<std::vector<TypeId>> interiorFreeTypes;
-    std::optional<std::vector<TypePackId>> interiorFreeTypePacks;
 };

 // Returns true iff the left scope encloses the right scope.  A Scope* equal to
--- a/Analysis/include/Luau/Simplify.h
+++ b/Analysis/include/Luau/Simplify.h
@ -19,13 +19,10 @@ struct SimplifyResult
    DenseHashSet<TypeId> blockedTypes;
 };

-SimplifyResult simplifyIntersection(NotNull<BuiltinTypes> builtinTypes, NotNull<TypeArena> arena, TypeId left, TypeId right);
+SimplifyResult simplifyIntersection(NotNull<BuiltinTypes> builtinTypes, NotNull<TypeArena> arena, TypeId ty, TypeId discriminant);
 SimplifyResult simplifyIntersection(NotNull<BuiltinTypes> builtinTypes, NotNull<TypeArena> arena, std::set<TypeId> parts);

-SimplifyResult simplifyUnion(NotNull<BuiltinTypes> builtinTypes, NotNull<TypeArena> arena, TypeId left, TypeId right);
-
-SimplifyResult simplifyIntersectWithTruthy(NotNull<BuiltinTypes> builtinTypes, NotNull<TypeArena> arena, TypeId target);
-SimplifyResult simplifyIntersectWithFalsy(NotNull<BuiltinTypes> builtinTypes, NotNull<TypeArena> arena, TypeId target);
+SimplifyResult simplifyUnion(NotNull<BuiltinTypes> builtinTypes, NotNull<TypeArena> arena, TypeId ty, TypeId discriminant);

 enum class Relation
 {
--- a/Analysis/include/Luau/Substitution.h
+++ b/Analysis/include/Luau/Substitution.h
@ -86,7 +86,6 @@ struct TarjanNode
 struct Tarjan
 {
    Tarjan();
-    virtual ~Tarjan() = default;

    // Vertices (types and type packs) are indexed, using pre-order traversal.
    DenseHashMap<TypeId, int> typeToIndex{nullptr};
@ -122,7 +121,7 @@ struct Tarjan
    void visitChildren(TypePackId tp, int index);

    void visitChild(TypeId ty);
-    void visitChild(TypePackId tp);
+    void visitChild(TypePackId ty);

    template<typename Ty>
    void visitChild(std::optional<Ty> ty)
@ -133,7 +132,7 @@ struct Tarjan

    // Visit the root vertex.
    TarjanResult visitRoot(TypeId ty);
-    TarjanResult visitRoot(TypePackId tp);
+    TarjanResult visitRoot(TypePackId ty);

    // Used to reuse the object for a new operation
    void clearTarjan(const TxnLog* log);
@ -151,12 +150,26 @@ struct Tarjan
    void visitSCC(int index);

    // Each subclass can decide to ignore some nodes.
-    virtual bool ignoreChildren(TypeId ty);
-    virtual bool ignoreChildren(TypePackId ty);
+    virtual bool ignoreChildren(TypeId ty)
+    {
+        return false;
+    }
+
+    virtual bool ignoreChildren(TypePackId ty)
+    {
+        return false;
+    }

    // Some subclasses might ignore children visit, but not other actions like replacing the children
-    virtual bool ignoreChildrenVisit(TypeId ty);
-    virtual bool ignoreChildrenVisit(TypePackId ty);
+    virtual bool ignoreChildrenVisit(TypeId ty)
+    {
+        return ignoreChildren(ty);
+    }
+
+    virtual bool ignoreChildrenVisit(TypePackId ty)
+    {
+        return ignoreChildren(ty);
+    }

    // Subclasses should say which vertices are dirty,
    // and what to do with dirty vertices.
@ -171,7 +184,6 @@ struct Tarjan
 struct Substitution : Tarjan
 {
 protected:
-    explicit Substitution(TypeArena* arena);
    Substitution(const TxnLog* log_, TypeArena* arena);

    /*
@ -220,23 +232,28 @@ public:
    virtual TypeId clean(TypeId ty) = 0;
    virtual TypePackId clean(TypePackId tp) = 0;

-protected:
    // Helper functions to create new types (used by subclasses)
    template<typename T>
-    TypeId addType(T tv)
+    TypeId addType(const T& tv)
    {
-        return arena->addType(std::move(tv));
+        return arena->addType(tv);
    }

    template<typename T>
-    TypePackId addTypePack(T tp)
+    TypePackId addTypePack(const T& tp)
    {
-        return arena->addTypePack(TypePackVar{std::move(tp)});
+        return arena->addTypePack(TypePackVar{tp});
    }

 private:
    template<typename Ty>
-    std::optional<Ty> replace(std::optional<Ty> ty);
+    std::optional<Ty> replace(std::optional<Ty> ty)
+    {
+        if (ty)
+            return replace(*ty);
+        else
+            return std::nullopt;
+    }
 };

 } // namespace Luau
--- a/Analysis/include/Luau/Subtyping.h
+++ b/Analysis/include/Luau/Subtyping.h
@ -22,7 +22,7 @@ struct InternalErrorReporter;

 class TypeIds;
 class Normalizer;
-struct NormalizedExternType;
+struct NormalizedClassType;
 struct NormalizedFunctionType;
 struct NormalizedStringType;
 struct NormalizedType;
@ -121,7 +121,7 @@ struct SubtypingEnvironment
    DenseHashMap<TypePackId, TypePackId> mappedGenericPacks{nullptr};

    /*
-     * See the test cyclic_tables_are_assumed_to_be_compatible_with_extern_types for
+     * See the test cyclic_tables_are_assumed_to_be_compatible_with_classes for
     * details.
     *
     * An empty value is equivalent to a nonexistent key.
@ -229,8 +229,9 @@ private:
    SubtypingResult isCovariantWith(SubtypingEnvironment& env, const TableType* subTable, const TableType* superTable, NotNull<Scope> scope);
    SubtypingResult isCovariantWith(SubtypingEnvironment& env, const MetatableType* subMt, const MetatableType* superMt, NotNull<Scope> scope);
    SubtypingResult isCovariantWith(SubtypingEnvironment& env, const MetatableType* subMt, const TableType* superTable, NotNull<Scope> scope);
-    SubtypingResult isCovariantWith(SubtypingEnvironment& env, const ExternType* subExternType, const ExternType* superExternType, NotNull<Scope> scope);
-    SubtypingResult isCovariantWith(SubtypingEnvironment& env, TypeId subTy, const ExternType* subExternType, TypeId superTy, const TableType* superTable, NotNull<Scope>);
+    SubtypingResult isCovariantWith(SubtypingEnvironment& env, const ClassType* subClass, const ClassType* superClass, NotNull<Scope> scope);
+    SubtypingResult
+    isCovariantWith(SubtypingEnvironment& env, TypeId subTy, const ClassType* subClass, TypeId superTy, const TableType* superTable, NotNull<Scope>);
    SubtypingResult isCovariantWith(
        SubtypingEnvironment& env,
        const FunctionType* subFunction,
@ -258,11 +259,11 @@ private:
    );
    SubtypingResult isCovariantWith(
        SubtypingEnvironment& env,
-        const NormalizedExternType& subExternType,
-        const NormalizedExternType& superExternType,
+        const NormalizedClassType& subClass,
+        const NormalizedClassType& superClass,
        NotNull<Scope> scope
    );
-    SubtypingResult isCovariantWith(SubtypingEnvironment& env, const NormalizedExternType& subExternType, const TypeIds& superTables, NotNull<Scope> scope);
+    SubtypingResult isCovariantWith(SubtypingEnvironment& env, const NormalizedClassType& subClass, const TypeIds& superTables, NotNull<Scope> scope);
    SubtypingResult isCovariantWith(
        SubtypingEnvironment& env,
        const NormalizedStringType& subString,
--- a/Analysis/include/Luau/TableLiteralInference.h
+++ b/Analysis/include/Luau/TableLiteralInference.h
@ -6,15 +6,12 @@
 #include "Luau/NotNull.h"
 #include "Luau/TypeFwd.h"

-#include <vector>
-
 namespace Luau
 {

 struct TypeArena;
 struct BuiltinTypes;
 struct Unifier2;
-struct Subtyping;
 class AstExpr;

 TypeId matchLiteralType(
@ -23,7 +20,6 @@ TypeId matchLiteralType(
    NotNull<BuiltinTypes> builtinTypes,
    NotNull<TypeArena> arena,
    NotNull<Unifier2> unifier,
-    NotNull<Subtyping> subtyping,
    TypeId expectedType,
    TypeId exprType,
    const AstExpr* expr,
--- a/Analysis/include/Luau/ToString.h
+++ b/Analysis/include/Luau/ToString.h
@ -44,7 +44,6 @@ struct ToStringOptions
    bool hideTableKind = false;                   // If true, all tables will be surrounded with plain '{}'
    bool hideNamedFunctionTypeParameters = false; // If true, type parameters of functions will be hidden at top-level.
    bool hideFunctionSelfArgument = false;        // If true, `self: X` will be omitted from the function signature if the function has self
-    bool hideTableAliasExpansions = false;        // If true, all table aliases will not be expanded
    bool useQuestionMarks = true;                 // If true, use a postfix ? for options, else write them out as unions that include nil.
    size_t maxTableLength = size_t(FInt::LuauTableTypeMaximumStringifierLength); // Only applied to TableTypes
    size_t maxTypeLength = size_t(FInt::LuauTypeMaximumStringifierLength);
--- a/Analysis/include/Luau/TxnLog.h
+++ b/Analysis/include/Luau/TxnLog.h
@ -65,10 +65,11 @@ T* getMutable(PendingTypePack* pending)
 // Log of what TypeIds we are rebinding, to be committed later.
 struct TxnLog
 {
-    explicit TxnLog()
+    explicit TxnLog(bool useScopes = false)
        : typeVarChanges(nullptr)
        , typePackChanges(nullptr)
        , ownedSeen()
+        , useScopes(useScopes)
        , sharedSeen(&ownedSeen)
    {
    }
@ -192,6 +193,16 @@ struct TxnLog
    // The pointer returned lives until `commit` or `clear` is called.
    PendingTypePack* changeLevel(TypePackId tp, TypeLevel newLevel);

+    // Queues the replacement of a type's scope with the provided scope.
+    //
+    // The pointer returned lives until `commit` or `clear` is called.
+    PendingType* changeScope(TypeId ty, NotNull<Scope> scope);
+
+    // Queues the replacement of a type pack's scope with the provided scope.
+    //
+    // The pointer returned lives until `commit` or `clear` is called.
+    PendingTypePack* changeScope(TypePackId tp, NotNull<Scope> scope);
+
    // Queues a replacement of a table type with another table type with a new
    // indexer.
    //
--- a/Analysis/include/Luau/Type.h
+++ b/Analysis/include/Luau/Type.h
@ -5,11 +5,10 @@

 #include "Luau/Ast.h"
 #include "Luau/Common.h"
+#include "Luau/Refinement.h"
 #include "Luau/DenseHash.h"
 #include "Luau/NotNull.h"
-#include "Luau/Polarity.h"
 #include "Luau/Predicate.h"
-#include "Luau/Refinement.h"
 #include "Luau/Unifiable.h"
 #include "Luau/Variant.h"
 #include "Luau/VecDeque.h"
@ -20,6 +19,7 @@
 #include <optional>
 #include <set>
 #include <string>
+#include <unordered_map>
 #include <vector>

 LUAU_FASTINT(LuauTableTypeMaximumStringifierLength)
@ -69,11 +69,11 @@ using Name = std::string;
 // A free type is one whose exact shape has yet to be fully determined.
 struct FreeType
 {
-    // New constructors
-    explicit FreeType(TypeLevel level, TypeId lowerBound, TypeId upperBound);
-    // This one got promoted to explicit
-    explicit FreeType(Scope* scope, TypeId lowerBound, TypeId upperBound, Polarity polarity = Polarity::Unknown);
-    explicit FreeType(Scope* scope, TypeLevel level, TypeId lowerBound, TypeId upperBound);
+    explicit FreeType(TypeLevel level);
+    explicit FreeType(Scope* scope);
+    FreeType(Scope* scope, TypeLevel level);
+
+    FreeType(Scope* scope, TypeId lowerBound, TypeId upperBound);

    int index;
    TypeLevel level;
@ -87,8 +87,6 @@ struct FreeType
    // Only used under local type inference
    TypeId lowerBound = nullptr;
    TypeId upperBound = nullptr;
-
-    Polarity polarity = Polarity::Unknown;
 };

 struct GenericType
@ -97,8 +95,8 @@ struct GenericType
    GenericType();

    explicit GenericType(TypeLevel level);
-    explicit GenericType(const Name& name, Polarity polarity = Polarity::Unknown);
-    explicit GenericType(Scope* scope, Polarity polarity = Polarity::Unknown);
+    explicit GenericType(const Name& name);
+    explicit GenericType(Scope* scope);

    GenericType(TypeLevel level, const Name& name);
    GenericType(Scope* scope, const Name& name);
@ -108,8 +106,6 @@ struct GenericType
    Scope* scope = nullptr;
    Name name;
    bool explicitName = false;
-
-    Polarity polarity = Polarity::Unknown;
 };

 // When an equality constraint is found, it is then "bound" to that type,
@ -287,7 +283,7 @@ struct MagicFunctionCallContext
 {
    NotNull<struct ConstraintSolver> solver;
    NotNull<const Constraint> constraint;
-    NotNull<const AstExprCall> callSite;
+    const class AstExprCall* callSite;
    TypePackId arguments;
    TypePackId result;
 };
@ -310,8 +306,7 @@ struct MagicFunctionTypeCheckContext

 struct MagicFunction
 {
-    virtual std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) = 0;
+    virtual std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) = 0;

    // Callback to allow custom typechecking of builtin function calls whose argument types
    // will only be resolved after constraint solving. For example, the arguments to string.format
@ -348,8 +343,10 @@ struct FunctionType
    );

    // Local monomorphic function
+    FunctionType(TypeLevel level, TypePackId argTypes, TypePackId retTypes, std::optional<FunctionDefinition> defn = {}, bool hasSelf = false);
    FunctionType(
        TypeLevel level,
+        Scope* scope,
        TypePackId argTypes,
        TypePackId retTypes,
        std::optional<FunctionDefinition> defn = {},
@ -366,6 +363,16 @@ struct FunctionType
        std::optional<FunctionDefinition> defn = {},
        bool hasSelf = false
    );
+    FunctionType(
+        TypeLevel level,
+        Scope* scope,
+        std::vector<TypeId> generics,
+        std::vector<TypePackId> genericPacks,
+        TypePackId argTypes,
+        TypePackId retTypes,
+        std::optional<FunctionDefinition> defn = {},
+        bool hasSelf = false
+    );

    std::optional<FunctionDefinition> definition;
    /// These should all be generic
@ -374,6 +381,7 @@ struct FunctionType
    std::vector<std::optional<FunctionArgument>> argNames;
    Tags tags;
    TypeLevel level;
+    Scope* scope = nullptr;
    TypePackId argTypes;
    TypePackId retTypes;
    std::shared_ptr<MagicFunction> magic = nullptr;
@ -383,7 +391,6 @@ struct FunctionType
    // this flag is used as an optimization to exit early from procedures that manipulate free or generic types.
    bool hasNoFreeOrGenericTypes = false;
    bool isCheckedFunction = false;
-    bool isDeprecatedFunction = false;
 };

 enum class TableState
@ -460,9 +467,7 @@ struct Property
    TypeId type() const;
    void setType(TypeId ty);

-    // If this property has a present `writeTy`, set it equal to the `readTy`.
-    // This is to ensure that if we normalize a property that has divergent
-    // read and write types, we make them converge (for now).
+    // Sets the write type of this property to the read type.
    void makeShared();

    bool isShared() const;
@ -507,6 +512,9 @@ struct TableType
    std::optional<TypeId> boundTo;
    Tags tags;

+    // Methods of this table that have an untyped self will use the same shared self type.
+    std::optional<TypeId> selfTy;
+
    // We track the number of as-yet-unadded properties to unsealed tables.
    // Some constraints will use this information to decide whether or not they
    // are able to dispatch.
@ -532,15 +540,15 @@ struct ClassUserData
    virtual ~ClassUserData() {}
 };

-/** The type of an external userdata exposed to Luau.
+/** The type of a class.
 *
- * Extern types behave like tables in many ways, but there are some important differences:
+ * Classes behave like tables in many ways, but there are some important differences:
 *
 * The properties of a class are always exactly known.
- * Extern types optionally have a parent type.
- * Two different extern types that share the same properties are nevertheless distinct and mutually incompatible.
+ * Classes optionally have a parent class.
+ * Two different classes that share the same properties are nevertheless distinct and mutually incompatible.
 */
-struct ExternType
+struct ClassType
 {
    using Props = TableType::Props;

@ -554,7 +562,7 @@ struct ExternType
    std::optional<Location> definitionLocation;
    std::optional<TableIndexer> indexer;

-    ExternType(
+    ClassType(
        Name name,
        Props props,
        std::optional<TypeId> parent,
@ -575,7 +583,7 @@ struct ExternType
    {
    }

-    ExternType(
+    ClassType(
        Name name,
        Props props,
        std::optional<TypeId> parent,
@ -609,6 +617,7 @@ struct UserDefinedFunctionData
    AstStatTypeFunction* definition = nullptr;

    DenseHashMap<Name, std::pair<AstStatTypeFunction*, size_t>> environment{""};
+    DenseHashMap<Name, AstStatTypeFunction*> environment_DEPRECATED{""};
 };

 /**
@ -775,7 +784,7 @@ using TypeVariant = Unifiable::Variant<
    FunctionType,
    TableType,
    MetatableType,
-    ExternType,
+    ClassType,
    AnyType,
    UnionType,
    IntersectionType,
@ -868,9 +877,6 @@ struct TypeFun
     */
    TypeId type;

-    // The location of where this TypeFun was defined, if available
-    std::optional<Location> definitionLocation;
-
    TypeFun() = default;

    explicit TypeFun(TypeId ty)
@ -878,23 +884,16 @@ struct TypeFun
    {
    }

-    TypeFun(std::vector<GenericTypeDefinition> typeParams, TypeId type, std::optional<Location> definitionLocation = std::nullopt)
+    TypeFun(std::vector<GenericTypeDefinition> typeParams, TypeId type)
        : typeParams(std::move(typeParams))
        , type(type)
-        , definitionLocation(definitionLocation)
    {
    }

-    TypeFun(
-        std::vector<GenericTypeDefinition> typeParams,
-        std::vector<GenericTypePackDefinition> typePackParams,
-        TypeId type,
-        std::optional<Location> definitionLocation = std::nullopt
-    )
+    TypeFun(std::vector<GenericTypeDefinition> typeParams, std::vector<GenericTypePackDefinition> typePackParams, TypeId type)
        : typeParams(std::move(typeParams))
        , typePackParams(std::move(typePackParams))
        , type(type)
-        , definitionLocation(definitionLocation)
    {
    }

@ -986,7 +985,7 @@ public:
    const TypeId threadType;
    const TypeId bufferType;
    const TypeId functionType;
-    const TypeId externType;
+    const TypeId classType;
    const TypeId tableType;
    const TypeId emptyTableType;
    const TypeId trueType;
@ -998,7 +997,6 @@ public:
    const TypeId noRefineType;
    const TypeId falsyType;
    const TypeId truthyType;
-    const TypeId notNilType;

    const TypeId optionalNumberType;
    const TypeId optionalStringType;
@ -1019,10 +1017,10 @@ TypeLevel* getMutableLevel(TypeId ty);

 std::optional<TypeLevel> getLevel(TypePackId tp);

-const Property* lookupExternTypeProp(const ExternType* cls, const Name& name);
+const Property* lookupClassProp(const ClassType* cls, const Name& name);

 // Whether `cls` is a subclass of `parent`
-bool isSubclass(const ExternType* cls, const ExternType* parent);
+bool isSubclass(const ClassType* cls, const ClassType* parent);

 Type* asMutable(TypeId ty);

@ -1199,7 +1197,7 @@ private:
    }
 };

-TypeId freshType(NotNull<TypeArena> arena, NotNull<BuiltinTypes> builtinTypes, Scope* scope, Polarity polarity = Polarity::Unknown);
+TypeId freshType(NotNull<TypeArena> arena, NotNull<BuiltinTypes> builtinTypes, Scope* scope);

 using TypeIdPredicate = std::function<std::optional<TypeId>(TypeId)>;
 std::vector<TypeId> filterMap(TypeId type, TypeIdPredicate predicate);
--- a/Analysis/include/Luau/TypeArena.h
+++ b/Analysis/include/Luau/TypeArena.h
@ -1,7 +1,6 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
 #pragma once

-#include "Luau/Polarity.h"
 #include "Luau/TypedAllocator.h"
 #include "Luau/Type.h"
 #include "Luau/TypePack.h"
@ -33,11 +32,11 @@ struct TypeArena

    TypeId addTV(Type&& tv);

-    TypeId freshType(NotNull<BuiltinTypes> builtins, TypeLevel level);
-    TypeId freshType(NotNull<BuiltinTypes> builtins, Scope* scope);
-    TypeId freshType(NotNull<BuiltinTypes> builtins, Scope* scope, TypeLevel level);
+    TypeId freshType(TypeLevel level);
+    TypeId freshType(Scope* scope);
+    TypeId freshType(Scope* scope, TypeLevel level);

-    TypePackId freshTypePack(Scope* scope, Polarity polarity = Polarity::Unknown);
+    TypePackId freshTypePack(Scope* scope);

    TypePackId addTypePack(std::initializer_list<TypeId> types);
    TypePackId addTypePack(std::vector<TypeId> types, std::optional<TypePackId> tail = {});
--- a/Analysis/include/Luau/TypeAttach.h
+++ b/Analysis/include/Luau/TypeAttach.h
@ -11,7 +11,7 @@ namespace Luau
 struct TypeRehydrationOptions
 {
    std::unordered_set<std::string> bannedNames;
-    bool expandExternTypeProps = false;
+    bool expandClassProps = false;
 };

 void attachTypeData(SourceModule& source, Module& result);
--- a/Analysis/include/Luau/TypeChecker2.h
+++ b/Analysis/include/Luau/TypeChecker2.h
@ -13,8 +13,6 @@
 #include "Luau/TypeOrPack.h"
 #include "Luau/TypeUtils.h"

-LUAU_FASTFLAG(LuauImproveTypePathsInErrors)
-
 namespace Luau
 {

@ -40,29 +38,18 @@ struct Reasonings

    std::string toString()
    {
-        if (FFlag::LuauImproveTypePathsInErrors && reasons.empty())
-            return "";
-
        // DenseHashSet ordering is entirely undefined, so we want to
        // sort the reasons here to achieve a stable error
        // stringification.
        std::sort(reasons.begin(), reasons.end());
-        std::string allReasons = FFlag::LuauImproveTypePathsInErrors ? "\nthis is because " : "";
+        std::string allReasons;
        bool first = true;
        for (const std::string& reason : reasons)
        {
-            if (FFlag::LuauImproveTypePathsInErrors)
-            {
-                if (reasons.size() > 1)
-                    allReasons += "\n\t * ";
-            }
+            if (first)
+                first = false;
            else
-            {
-                if (first)
-                    first = false;
-                else
-                    allReasons += "\n\t";
-            }
+                allReasons += "\n\t";

            allReasons += reason;
        }
@ -76,7 +63,7 @@ void check(
    NotNull<BuiltinTypes> builtinTypes,
    NotNull<Simplifier> simplifier,
    NotNull<TypeFunctionRuntime> typeFunctionRuntime,
-    NotNull<UnifierSharedState> unifierState,
+    NotNull<UnifierSharedState> sharedState,
    NotNull<TypeCheckLimits> limits,
    DcrLogger* logger,
    const SourceModule& sourceModule,
@ -129,14 +116,14 @@ private:
    std::optional<StackPusher> pushStack(AstNode* node);
    void checkForInternalTypeFunction(TypeId ty, Location location);
    TypeId checkForTypeFunctionInhabitance(TypeId instance, Location location);
-    TypePackId lookupPack(AstExpr* expr) const;
+    TypePackId lookupPack(AstExpr* expr);
    TypeId lookupType(AstExpr* expr);
    TypeId lookupAnnotation(AstType* annotation);
-    std::optional<TypePackId> lookupPackAnnotation(AstTypePack* annotation) const;
-    TypeId lookupExpectedType(AstExpr* expr) const;
-    TypePackId lookupExpectedPack(AstExpr* expr, TypeArena& arena) const;
+    std::optional<TypePackId> lookupPackAnnotation(AstTypePack* annotation);
+    TypeId lookupExpectedType(AstExpr* expr);
+    TypePackId lookupExpectedPack(AstExpr* expr, TypeArena& arena);
    TypePackId reconstructPack(AstArray<AstExpr*> exprs, TypeArena& arena);
-    Scope* findInnermostScope(Location location) const;
+    Scope* findInnermostScope(Location location);
    void visit(AstStat* stat);
    void visit(AstStatIf* ifStatement);
    void visit(AstStatWhile* whileStatement);
@ -160,7 +147,7 @@ private:
    void visit(AstTypeList types);
    void visit(AstStatDeclareFunction* stat);
    void visit(AstStatDeclareGlobal* stat);
-    void visit(AstStatDeclareExternType* stat);
+    void visit(AstStatDeclareClass* stat);
    void visit(AstStatError* stat);
    void visit(AstExpr* expr, ValueContext context);
    void visit(AstExprGroup* expr, ValueContext context);
@ -173,7 +160,7 @@ private:
    void visit(AstExprVarargs* expr);
    void visitCall(AstExprCall* call);
    void visit(AstExprCall* call);
-    std::optional<TypeId> tryStripUnionFromNil(TypeId ty) const;
+    std::optional<TypeId> tryStripUnionFromNil(TypeId ty);
    TypeId stripFromNilAndReport(TypeId ty, const Location& location);
    void visitExprName(AstExpr* expr, Location location, const std::string& propName, ValueContext context, TypeId astIndexExprTy);
    void visit(AstExprIndexName* indexName, ValueContext context);
@ -188,7 +175,7 @@ private:
    void visit(AstExprInterpString* interpString);
    void visit(AstExprError* expr);
    TypeId flattenPack(TypePackId pack);
-    void visitGenerics(AstArray<AstGenericType*> generics, AstArray<AstGenericTypePack*> genericPacks);
+    void visitGenerics(AstArray<AstGenericType> generics, AstArray<AstGenericTypePack> genericPacks);
    void visit(AstType* ty);
    void visit(AstTypeReference* ty);
    void visit(AstTypeTable* table);
--- a/Analysis/include/Luau/TypeFunction.h
+++ b/Analysis/include/Luau/TypeFunction.h
@ -48,9 +48,6 @@ struct TypeFunctionRuntime
    // Evaluation of type functions should only be performed in the absence of parse errors in the source module
    bool allowEvaluation = true;

-    // Root scope in which the type function operates in, set up by ConstraintGenerator
-    ScopePtr rootScope;
-
    // Output created by 'print' function
    std::vector<std::string> messages;

@ -155,9 +152,6 @@ struct TypeFunction

    /// The reducer function for the type function.
    ReducerFunction<TypeId> reducer;
-
-    /// If true, this type function can reduce even if it is parameterized on a generic.
-    bool canReduceGenerics = false;
 };

 /// Represents a type function that may be applied to map a series of types and
@ -170,9 +164,6 @@ struct TypePackFunction

    /// The reducer function for the type pack function.
    ReducerFunction<TypePackId> reducer;
-
-    /// If true, this type function can reduce even if it is parameterized on a generic.
-    bool canReduceGenerics = false;
 };

 struct FunctionGraphReductionResult
@ -183,7 +174,6 @@ struct FunctionGraphReductionResult
    DenseHashSet<TypePackId> blockedPacks{nullptr};
    DenseHashSet<TypeId> reducedTypes{nullptr};
    DenseHashSet<TypePackId> reducedPacks{nullptr};
-    DenseHashSet<TypeId> irreducibleTypes{nullptr};
 };

 /**
@ -251,11 +241,6 @@ struct BuiltinTypeFunctions
    TypeFunction indexFunc;
    TypeFunction rawgetFunc;

-    TypeFunction setmetatableFunc;
-    TypeFunction getmetatableFunc;
-
-    TypeFunction weakoptionalFunc;
-
    void addToScope(NotNull<TypeArena> arena, NotNull<Scope> scope) const;
 };

--- a/Analysis/include/Luau/TypeFunctionRuntime.h
+++ b/Analysis/include/Luau/TypeFunctionRuntime.h
@ -3,7 +3,6 @@

 #include "Luau/Common.h"
 #include "Luau/Variant.h"
-#include "Luau/TypeFwd.h"

 #include <optional>
 #include <string>
@ -205,7 +204,7 @@ struct TypeFunctionTableType
    std::optional<TypeFunctionTypeId> metatable;
 };

-struct TypeFunctionExternType
+struct TypeFunctionClassType
 {
    using Name = std::string;
    using Props = std::map<Name, TypeFunctionProperty>;
@ -216,13 +215,9 @@ struct TypeFunctionExternType

    std::optional<TypeFunctionTypeId> metatable; // metaclass?

-    // this was mistaken, and we should actually be keeping separate read/write types here.
-    std::optional<TypeFunctionTypeId> parent_DEPRECATED;
+    std::optional<TypeFunctionTypeId> parent;

-    std::optional<TypeFunctionTypeId> readParent;
-    std::optional<TypeFunctionTypeId> writeParent;
-
-    TypeId externTy;
+    std::string name;
 };

 struct TypeFunctionGenericType
@ -244,7 +239,7 @@ using TypeFunctionTypeVariant = Luau::Variant<
    TypeFunctionNegationType,
    TypeFunctionFunctionType,
    TypeFunctionTableType,
-    TypeFunctionExternType,
+    TypeFunctionClassType,
    TypeFunctionGenericType>;

 struct TypeFunctionType
--- a/Analysis/include/Luau/TypeFunctionRuntimeBuilder.h
+++ b/Analysis/include/Luau/TypeFunctionRuntimeBuilder.h
@ -28,12 +28,20 @@ struct TypeFunctionRuntimeBuilderState
 {
    NotNull<TypeFunctionContext> ctx;

+    // Mapping of class name to ClassType
+    // Invariant: users can not create a new class types -> any class types that get deserialized must have been an argument to the type function
+    // Using this invariant, whenever a ClassType is serialized, we can put it into this map
+    // whenever a ClassType is deserialized, we can use this map to return the corresponding value
+    DenseHashMap<std::string, TypeId> classesSerialized{{}};
+
    // List of errors that occur during serialization/deserialization
-    // At every iteration of serialization/deserialization, if this list.size() != 0, we halt the process
+    // At every iteration of serialization/deserialzation, if this list.size() != 0, we halt the process
    std::vector<std::string> errors{};

    TypeFunctionRuntimeBuilderState(NotNull<TypeFunctionContext> ctx)
        : ctx(ctx)
+        , classesSerialized({})
+        , errors({})
    {
    }
 };
--- a/Analysis/include/Luau/TypeFwd.h
+++ b/Analysis/include/Luau/TypeFwd.h
@ -29,7 +29,7 @@ struct SingletonType;
 struct FunctionType;
 struct TableType;
 struct MetatableType;
-struct ExternType;
+struct ClassType;
 struct AnyType;
 struct UnionType;
 struct IntersectionType;
--- a/Analysis/include/Luau/TypeInfer.h
+++ b/Analysis/include/Luau/TypeInfer.h
@ -90,11 +90,11 @@ struct TypeChecker
    ControlFlow check(const ScopePtr& scope, TypeId ty, const ScopePtr& funScope, const AstStatLocalFunction& function);
    ControlFlow check(const ScopePtr& scope, const AstStatTypeAlias& typealias);
    ControlFlow check(const ScopePtr& scope, const AstStatTypeFunction& typefunction);
-    ControlFlow check(const ScopePtr& scope, const AstStatDeclareExternType& declaredExternType);
+    ControlFlow check(const ScopePtr& scope, const AstStatDeclareClass& declaredClass);
    ControlFlow check(const ScopePtr& scope, const AstStatDeclareFunction& declaredFunction);

    void prototype(const ScopePtr& scope, const AstStatTypeAlias& typealias, int subLevel = 0);
-    void prototype(const ScopePtr& scope, const AstStatDeclareExternType& declaredExternType);
+    void prototype(const ScopePtr& scope, const AstStatDeclareClass& declaredClass);

    ControlFlow checkBlock(const ScopePtr& scope, const AstStatBlock& statement);
    ControlFlow checkBlockWithoutRecursionCheck(const ScopePtr& scope, const AstStatBlock& statement);
@ -130,7 +130,6 @@ struct TypeChecker
        const PredicateVec& predicates = {}
    );
    WithPredicate<TypeId> checkExpr(const ScopePtr& scope, const AstExprBinary& expr, std::optional<TypeId> expectedType = std::nullopt);
-    WithPredicate<TypeId> checkExpr_DEPRECATED(const ScopePtr& scope, const AstExprBinary& expr, std::optional<TypeId> expectedType = std::nullopt);
    WithPredicate<TypeId> checkExpr(const ScopePtr& scope, const AstExprTypeAssertion& expr);
    WithPredicate<TypeId> checkExpr(const ScopePtr& scope, const AstExprError& expr);
    WithPredicate<TypeId> checkExpr(const ScopePtr& scope, const AstExprIfElse& expr, std::optional<TypeId> expectedType = std::nullopt);
@ -400,8 +399,8 @@ private:
        const ScopePtr& scope,
        std::optional<TypeLevel> levelOpt,
        const AstNode& node,
-        const AstArray<AstGenericType*>& genericNames,
-        const AstArray<AstGenericTypePack*>& genericPackNames,
+        const AstArray<AstGenericType>& genericNames,
+        const AstArray<AstGenericTypePack>& genericPackNames,
        bool useCache = false
    );

@ -487,7 +486,7 @@ private:
    /**
     * A set of incorrect class definitions which is used to avoid a second-pass analysis.
     */
-    DenseHashSet<const AstStatDeclareExternType*> incorrectExternTypeDefinitions{nullptr};
+    DenseHashSet<const AstStatDeclareClass*> incorrectClassDefinitions{nullptr};

    std::vector<std::pair<TypeId, ScopePtr>> deferredQuantification;
 };
--- a/Analysis/include/Luau/TypePack.h
+++ b/Analysis/include/Luau/TypePack.h
@ -1,12 +1,11 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
 #pragma once

-#include "Luau/Common.h"
-#include "Luau/NotNull.h"
-#include "Luau/Polarity.h"
-#include "Luau/TypeFwd.h"
 #include "Luau/Unifiable.h"
 #include "Luau/Variant.h"
+#include "Luau/TypeFwd.h"
+#include "Luau/NotNull.h"
+#include "Luau/Common.h"

 #include <optional>
 #include <set>
@ -27,14 +26,12 @@ struct TypeFunctionInstanceTypePack;
 struct FreeTypePack
 {
    explicit FreeTypePack(TypeLevel level);
-    explicit FreeTypePack(Scope* scope, Polarity polarity = Polarity::Unknown);
+    explicit FreeTypePack(Scope* scope);
    FreeTypePack(Scope* scope, TypeLevel level);

    int index;
    TypeLevel level;
    Scope* scope = nullptr;
-
-    Polarity polarity = Polarity::Unknown;
 };

 struct GenericTypePack
@ -43,7 +40,7 @@ struct GenericTypePack
    GenericTypePack();
    explicit GenericTypePack(TypeLevel level);
    explicit GenericTypePack(const Name& name);
-    explicit GenericTypePack(Scope* scope, Polarity polarity = Polarity::Unknown);
+    explicit GenericTypePack(Scope* scope);
    GenericTypePack(TypeLevel level, const Name& name);
    GenericTypePack(Scope* scope, const Name& name);

@ -52,8 +49,6 @@ struct GenericTypePack
    Scope* scope = nullptr;
    Name name;
    bool explicitName = false;
-
-    Polarity polarity = Polarity::Unknown;
 };

 using BoundTypePack = Unifiable::Bound<TypePackId>;
@ -105,9 +100,9 @@ struct TypeFunctionInstanceTypePack

 struct TypePackVar
 {
-    explicit TypePackVar(const TypePackVariant& tp);
-    explicit TypePackVar(TypePackVariant&& tp);
-    TypePackVar(TypePackVariant&& tp, bool persistent);
+    explicit TypePackVar(const TypePackVariant& ty);
+    explicit TypePackVar(TypePackVariant&& ty);
+    TypePackVar(TypePackVariant&& ty, bool persistent);

    bool operator==(const TypePackVar& rhs) const;

@ -174,7 +169,6 @@ struct TypePackIterator

 private:
    TypePackId currentTypePack = nullptr;
-    TypePackId tailCycleCheck = nullptr;
    const TypePack* tp = nullptr;
    size_t currentIndex = 0;

@ -185,8 +179,6 @@ TypePackIterator begin(TypePackId tp);
 TypePackIterator begin(TypePackId tp, const TxnLog* log);
 TypePackIterator end(TypePackId tp);

-TypePackId getTail(TypePackId tp);
-
 using SeenSet = std::set<std::pair<const void*, const void*>>;

 bool areEqual(SeenSet& seen, const TypePackVar& lhs, const TypePackVar& rhs);
--- a/Analysis/include/Luau/TypePath.h
+++ b/Analysis/include/Luau/TypePath.h
@ -42,19 +42,9 @@ struct Property
 /// element.
 struct Index
 {
-    enum class Variant
-    {
-        Pack,
-        Union,
-        Intersection
-    };
-
    /// The 0-based index to use for the lookup.
    size_t index;

-    /// The sort of thing we're indexing from, this is used in stringifying the type path for errors.
-    Variant variant;
-
    bool operator==(const Index& other) const;
 };

@ -215,9 +205,6 @@ using Path = TypePath::Path;
 /// terribly clear to end users of the Luau type system.
 std::string toString(const TypePath::Path& path, bool prefixDot = false);

-/// Converts a Path to a human readable string for error reporting.
-std::string toStringHuman(const TypePath::Path& path);
-
 std::optional<TypeOrPack> traverse(TypeId root, const Path& path, NotNull<BuiltinTypes> builtinTypes);
 std::optional<TypeOrPack> traverse(TypePackId root, const Path& path, NotNull<BuiltinTypes> builtinTypes);

--- a/Analysis/include/Luau/TypeUtils.h
+++ b/Analysis/include/Luau/TypeUtils.h
@ -40,7 +40,7 @@ struct InConditionalContext
    TypeContext* typeContext;
    TypeContext oldValue;

-    explicit InConditionalContext(TypeContext* c)
+    InConditionalContext(TypeContext* c)
        : typeContext(c)
        , oldValue(*c)
    {
@ -289,6 +289,4 @@ std::vector<TypeId> findBlockedArgTypesIn(AstExprCall* expr, NotNull<DenseHashMa
 */
 void trackInteriorFreeType(Scope* scope, TypeId ty);

-void trackInteriorFreeTypePack(Scope* scope, TypePackId tp);
-
 } // namespace Luau
--- a/Analysis/include/Luau/Unifier.h
+++ b/Analysis/include/Luau/Unifier.h
@ -93,6 +93,10 @@ struct Unifier

    Unifier(NotNull<Normalizer> normalizer, NotNull<Scope> scope, const Location& location, Variance variance, TxnLog* parentLog = nullptr);

+    // Configure the Unifier to test for scope subsumption via embedded Scope
+    // pointers rather than TypeLevels.
+    void enableNewSolver();
+
    // Test whether the two type vars unify.  Never commits the result.
    ErrorVec canUnify(TypeId subTy, TypeId superTy);
    ErrorVec canUnify(TypePackId subTy, TypePackId superTy, bool isFunctionCall = false);
@ -140,7 +144,7 @@ private:
    void tryUnifyTables(TypeId subTy, TypeId superTy, bool isIntersection = false, const LiteralProperties* aliasableMap = nullptr);
    void tryUnifyScalarShape(TypeId subTy, TypeId superTy, bool reversed);
    void tryUnifyWithMetatable(TypeId subTy, TypeId superTy, bool reversed);
-    void tryUnifyWithExternType(TypeId subTy, TypeId superTy, bool reversed);
+    void tryUnifyWithClass(TypeId subTy, TypeId superTy, bool reversed);
    void tryUnifyNegations(TypeId subTy, TypeId superTy);

    TypePackId tryApplyOverloadedFunction(TypeId function, const NormalizedFunctionType& overloads, TypePackId args);
@ -165,6 +169,7 @@ private:

    std::optional<TypeId> findTablePropertyRespectingMeta(TypeId lhsType, Name name);

+    TxnLog combineLogsIntoIntersection(std::vector<TxnLog> logs);
    TxnLog combineLogsIntoUnion(std::vector<TxnLog> logs);

 public:
@ -190,6 +195,11 @@ private:

    // Available after regular type pack unification errors
    std::optional<int> firstPackErrorPos;
+
+    // If true, we do a bunch of small things differently to work better with
+    // the new type inference engine. Most notably, we use the Scope hierarchy
+    // directly rather than using TypeLevels.
+    bool useNewSolver = false;
 };

 void promoteTypeLevels(TxnLog& log, const TypeArena* arena, TypeLevel minLevel, Scope* outerScope, bool useScope, TypePackId tp);
--- a/Analysis/include/Luau/Unifier2.h
+++ b/Analysis/include/Luau/Unifier2.h
@ -44,12 +44,6 @@ struct Unifier2
    // Mapping from generic type packs to `TypePack`s of free types to be used in instantiation.
    DenseHashMap<TypePackId, TypePackId> genericPackSubstitutions{nullptr};

-    // Unification sometimes results in the creation of new free types.
-    // We collect them here so that other systems can perform necessary
-    // bookkeeping.
-    std::vector<TypeId> newFreshTypes;
-    std::vector<TypePackId> newFreshTypePacks;
-
    int recursionCount = 0;
    int recursionLimit = 0;

@ -93,9 +87,6 @@ struct Unifier2
    bool unify(const AnyType* subAny, const TableType* superTable);
    bool unify(const TableType* subTable, const AnyType* superAny);

-    bool unify(const MetatableType* subMetatable, const AnyType*);
-    bool unify(const AnyType*, const MetatableType* superMetatable);
-
    // TODO think about this one carefully.  We don't do unions or intersections of type packs
    bool unify(TypePackId subTp, TypePackId superTp);

@ -119,9 +110,6 @@ private:
    // Returns true if needle occurs within haystack already.  ie if we bound
    // needle to haystack, would a cyclic TypePack result?
    OccursCheckResult occursCheck(DenseHashSet<TypePackId>& seen, TypePackId needle, TypePackId haystack);
-
-    TypeId freshType(NotNull<Scope> scope, Polarity polarity);
-    TypePackId freshTypePack(NotNull<Scope> scope, Polarity polarity);
 };

 } // namespace Luau
--- a/Analysis/include/Luau/UnifierSharedState.h
+++ b/Analysis/include/Luau/UnifierSharedState.h
@ -49,26 +49,6 @@ struct UnifierSharedState
    DenseHashSet<TypePackId> tempSeenTp{nullptr};

    UnifierCounters counters;
-
-    bool reentrantTypeReduction = false;
-};
-
-struct TypeReductionRentrancyGuard final
-{
-    explicit TypeReductionRentrancyGuard(NotNull<UnifierSharedState> sharedState)
-        : sharedState{sharedState}
-    {
-        sharedState->reentrantTypeReduction = true;
-    }
-    ~TypeReductionRentrancyGuard()
-    {
-        sharedState->reentrantTypeReduction = false;
-    }
-    TypeReductionRentrancyGuard(const TypeReductionRentrancyGuard&) = delete;
-    TypeReductionRentrancyGuard(TypeReductionRentrancyGuard&&) = delete;
-
-private:
-    NotNull<UnifierSharedState> sharedState;
 };

 } // namespace Luau
--- a/Analysis/include/Luau/VisitType.h
+++ b/Analysis/include/Luau/VisitType.h
@ -126,7 +126,7 @@ struct GenericTypeVisitor
    {
        return visit(ty);
    }
-    virtual bool visit(TypeId ty, const ExternType& etv)
+    virtual bool visit(TypeId ty, const ClassType& ctv)
    {
        return visit(ty);
    }
@ -313,11 +313,11 @@ struct GenericTypeVisitor
                traverse(mtv->metatable);
            }
        }
-        else if (auto etv = get<ExternType>(ty))
+        else if (auto ctv = get<ClassType>(ty))
        {
-            if (visit(ty, *etv))
+            if (visit(ty, *ctv))
            {
-                for (const auto& [name, prop] : etv->props)
+                for (const auto& [name, prop] : ctv->props)
                {
                    if (FFlag::LuauSolverV2)
                    {
@ -335,16 +335,16 @@ struct GenericTypeVisitor
                        traverse(prop.type());
                }

-                if (etv->parent)
-                    traverse(*etv->parent);
+                if (ctv->parent)
+                    traverse(*ctv->parent);

-                if (etv->metatable)
-                    traverse(*etv->metatable);
+                if (ctv->metatable)
+                    traverse(*ctv->metatable);

-                if (etv->indexer)
+                if (ctv->indexer)
                {
-                    traverse(etv->indexer->indexType);
-                    traverse(etv->indexer->indexResultType);
+                    traverse(ctv->indexer->indexType);
+                    traverse(ctv->indexer->indexResultType);
                }
            }
        }
@ -396,7 +396,7 @@ struct GenericTypeVisitor
                traverse(unwrapped);

            // Visiting into LazyType that hasn't been unwrapped may necessarily cause infinite expansion, so we don't do that on purpose.
-            // Asserting also makes no sense, because the type _will_ happen here, most likely as a property of some ExternType
+            // Asserting also makes no sense, because the type _will_ happen here, most likely as a property of some ClassType
            // that doesn't need to be expanded.
        }
        else if (auto stv = get<SingletonType>(ty))
--- a/Analysis/src/AnyTypeSummary.cpp
+++ b/Analysis/src/AnyTypeSummary.cpp
@ -0,0 +1,902 @@
+// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
+#include "Luau/AnyTypeSummary.h"
+
+#include "Luau/BuiltinDefinitions.h"
+#include "Luau/Clone.h"
+#include "Luau/Common.h"
+#include "Luau/Config.h"
+#include "Luau/ConstraintGenerator.h"
+#include "Luau/ConstraintSolver.h"
+#include "Luau/DataFlowGraph.h"
+#include "Luau/DcrLogger.h"
+#include "Luau/Module.h"
+#include "Luau/Parser.h"
+#include "Luau/Scope.h"
+#include "Luau/StringUtils.h"
+#include "Luau/TimeTrace.h"
+#include "Luau/ToString.h"
+#include "Luau/Transpiler.h"
+#include "Luau/TypeArena.h"
+#include "Luau/TypeChecker2.h"
+#include "Luau/NonStrictTypeChecker.h"
+#include "Luau/TypeInfer.h"
+#include "Luau/Variant.h"
+#include "Luau/VisitType.h"
+#include "Luau/TypePack.h"
+#include "Luau/TypeOrPack.h"
+
+#include <algorithm>
+#include <memory>
+#include <chrono>
+#include <condition_variable>
+#include <exception>
+#include <mutex>
+#include <stdexcept>
+#include <string>
+#include <iostream>
+
+
+#include <stdio.h>
+
+LUAU_FASTFLAGVARIABLE(StudioReportLuauAny2);
+LUAU_FASTINTVARIABLE(LuauAnySummaryRecursionLimit, 300);
+
+LUAU_FASTFLAG(DebugLuauMagicTypes);
+
+namespace Luau
+{
+
+void AnyTypeSummary::traverse(const Module* module, AstStat* src, NotNull<BuiltinTypes> builtinTypes)
+{
+    visit(findInnerMostScope(src->location, module), src, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStat* stat, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    RecursionLimiter limiter{&recursionCount, FInt::LuauAnySummaryRecursionLimit};
+
+    if (auto s = stat->as<AstStatBlock>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto i = stat->as<AstStatIf>())
+        return visit(scope, i, module, builtinTypes);
+    else if (auto s = stat->as<AstStatWhile>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto s = stat->as<AstStatRepeat>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto r = stat->as<AstStatReturn>())
+        return visit(scope, r, module, builtinTypes);
+    else if (auto e = stat->as<AstStatExpr>())
+        return visit(scope, e, module, builtinTypes);
+    else if (auto s = stat->as<AstStatLocal>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto s = stat->as<AstStatFor>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto s = stat->as<AstStatForIn>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto a = stat->as<AstStatAssign>())
+        return visit(scope, a, module, builtinTypes);
+    else if (auto a = stat->as<AstStatCompoundAssign>())
+        return visit(scope, a, module, builtinTypes);
+    else if (auto f = stat->as<AstStatFunction>())
+        return visit(scope, f, module, builtinTypes);
+    else if (auto f = stat->as<AstStatLocalFunction>())
+        return visit(scope, f, module, builtinTypes);
+    else if (auto a = stat->as<AstStatTypeAlias>())
+        return visit(scope, a, module, builtinTypes);
+    else if (auto s = stat->as<AstStatDeclareGlobal>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto s = stat->as<AstStatDeclareFunction>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto s = stat->as<AstStatDeclareClass>())
+        return visit(scope, s, module, builtinTypes);
+    else if (auto s = stat->as<AstStatError>())
+        return visit(scope, s, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatBlock* block, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    RecursionCounter counter{&recursionCount};
+
+    if (recursionCount >= FInt::LuauAnySummaryRecursionLimit)
+        return; // don't report
+
+    for (AstStat* stat : block->body)
+        visit(scope, stat, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatIf* ifStatement, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    if (ifStatement->thenbody)
+    {
+        const Scope* thenScope = findInnerMostScope(ifStatement->thenbody->location, module);
+        visit(thenScope, ifStatement->thenbody, module, builtinTypes);
+    }
+
+    if (ifStatement->elsebody)
+    {
+        const Scope* elseScope = findInnerMostScope(ifStatement->elsebody->location, module);
+        visit(elseScope, ifStatement->elsebody, module, builtinTypes);
+    }
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatWhile* while_, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    const Scope* whileScope = findInnerMostScope(while_->location, module);
+    visit(whileScope, while_->body, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatRepeat* repeat, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    const Scope* repeatScope = findInnerMostScope(repeat->location, module);
+    visit(repeatScope, repeat->body, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatReturn* ret, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    const Scope* retScope = findInnerMostScope(ret->location, module);
+
+    auto ctxNode = getNode(rootSrc, ret);
+    bool seenTP = false;
+
+    for (auto val : ret->list)
+    {
+        if (isAnyCall(retScope, val, module, builtinTypes))
+        {
+            TelemetryTypePair types;
+            types.inferredType = toString(lookupType(val, module, builtinTypes));
+            TypeInfo ti{Pattern::FuncApp, toString(ctxNode), types};
+            typeInfo.push_back(ti);
+        }
+
+        if (isAnyCast(retScope, val, module, builtinTypes))
+        {
+            if (auto cast = val->as<AstExprTypeAssertion>())
+            {
+                TelemetryTypePair types;
+
+                types.annotatedType = toString(lookupAnnotation(cast->annotation, module, builtinTypes));
+                types.inferredType = toString(lookupType(cast->expr, module, builtinTypes));
+
+                TypeInfo ti{Pattern::Casts, toString(ctxNode), types};
+                typeInfo.push_back(ti);
+            }
+        }
+
+        if (ret->list.size > 1 && !seenTP)
+        {
+            if (containsAny(retScope->returnType))
+            {
+                seenTP = true;
+
+                TelemetryTypePair types;
+
+                types.inferredType = toString(retScope->returnType);
+
+                TypeInfo ti{Pattern::TypePk, toString(ctxNode), types};
+                typeInfo.push_back(ti);
+            }
+        }
+    }
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatLocal* local, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    auto ctxNode = getNode(rootSrc, local);
+
+    TypePackId values = reconstructTypePack(local->values, module, builtinTypes);
+    auto [head, tail] = flatten(values);
+
+    size_t posn = 0;
+    for (AstLocal* loc : local->vars)
+    {
+        if (local->vars.data[0] == loc && posn < local->values.size)
+        {
+            if (loc->annotation)
+            {
+                auto annot = lookupAnnotation(loc->annotation, module, builtinTypes);
+                if (containsAny(annot))
+                {
+                    TelemetryTypePair types;
+
+                    types.annotatedType = toString(annot);
+                    types.inferredType = toString(lookupType(local->values.data[posn], module, builtinTypes));
+
+                    TypeInfo ti{Pattern::VarAnnot, toString(ctxNode), types};
+                    typeInfo.push_back(ti);
+                }
+            }
+
+            const AstExprTypeAssertion* maybeRequire = local->values.data[posn]->as<AstExprTypeAssertion>();
+            if (!maybeRequire)
+                continue;
+
+            if (std::min(local->values.size - 1, posn) < head.size())
+            {
+                if (isAnyCast(scope, local->values.data[posn], module, builtinTypes))
+                {
+                    TelemetryTypePair types;
+
+                    types.inferredType = toString(head[std::min(local->values.size - 1, posn)]);
+
+                    TypeInfo ti{Pattern::Casts, toString(ctxNode), types};
+                    typeInfo.push_back(ti);
+                }
+            }
+        }
+        else
+        {
+
+            if (std::min(local->values.size - 1, posn) < head.size())
+            {
+                if (loc->annotation)
+                {
+                    auto annot = lookupAnnotation(loc->annotation, module, builtinTypes);
+                    if (containsAny(annot))
+                    {
+                        TelemetryTypePair types;
+
+                        types.annotatedType = toString(annot);
+                        types.inferredType = toString(head[std::min(local->values.size - 1, posn)]);
+
+                        TypeInfo ti{Pattern::VarAnnot, toString(ctxNode), types};
+                        typeInfo.push_back(ti);
+                    }
+                }
+            }
+            else
+            {
+                if (tail)
+                {
+                    if (containsAny(*tail))
+                    {
+                        TelemetryTypePair types;
+
+                        types.inferredType = toString(*tail);
+
+                        TypeInfo ti{Pattern::VarAny, toString(ctxNode), types};
+                        typeInfo.push_back(ti);
+                    }
+                }
+            }
+        }
+
+        ++posn;
+    }
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatFor* for_, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    const Scope* forScope = findInnerMostScope(for_->location, module);
+    visit(forScope, for_->body, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatForIn* forIn, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    const Scope* loopScope = findInnerMostScope(forIn->location, module);
+    visit(loopScope, forIn->body, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatAssign* assign, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    auto ctxNode = getNode(rootSrc, assign);
+
+    TypePackId values = reconstructTypePack(assign->values, module, builtinTypes);
+    auto [head, tail] = flatten(values);
+
+    size_t posn = 0;
+    for (AstExpr* var : assign->vars)
+    {
+        TypeId tp = lookupType(var, module, builtinTypes);
+        if (containsAny(tp))
+        {
+            TelemetryTypePair types;
+
+            types.annotatedType = toString(tp);
+
+            auto loc = std::min(assign->vars.size - 1, posn);
+            if (head.size() >= assign->vars.size && posn < head.size())
+            {
+                types.inferredType = toString(head[posn]);
+            }
+            else if (loc < head.size())
+                types.inferredType = toString(head[loc]);
+            else
+                types.inferredType = toString(builtinTypes->nilType);
+
+            TypeInfo ti{Pattern::Assign, toString(ctxNode), types};
+            typeInfo.push_back(ti);
+        }
+        ++posn;
+    }
+
+    for (AstExpr* val : assign->values)
+    {
+        if (isAnyCall(scope, val, module, builtinTypes))
+        {
+            TelemetryTypePair types;
+
+            types.inferredType = toString(lookupType(val, module, builtinTypes));
+
+            TypeInfo ti{Pattern::FuncApp, toString(ctxNode), types};
+            typeInfo.push_back(ti);
+        }
+
+        if (isAnyCast(scope, val, module, builtinTypes))
+        {
+            if (auto cast = val->as<AstExprTypeAssertion>())
+            {
+                TelemetryTypePair types;
+
+                types.annotatedType = toString(lookupAnnotation(cast->annotation, module, builtinTypes));
+                types.inferredType = toString(lookupType(val, module, builtinTypes));
+
+                TypeInfo ti{Pattern::Casts, toString(ctxNode), types};
+                typeInfo.push_back(ti);
+            }
+        }
+    }
+
+    if (tail)
+    {
+        if (containsAny(*tail))
+        {
+            TelemetryTypePair types;
+
+            types.inferredType = toString(*tail);
+
+            TypeInfo ti{Pattern::Assign, toString(ctxNode), types};
+            typeInfo.push_back(ti);
+        }
+    }
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatCompoundAssign* assign, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    auto ctxNode = getNode(rootSrc, assign);
+
+    TelemetryTypePair types;
+
+    types.inferredType = toString(lookupType(assign->value, module, builtinTypes));
+    types.annotatedType = toString(lookupType(assign->var, module, builtinTypes));
+
+    if (module->astTypes.contains(assign->var))
+    {
+        if (containsAny(*module->astTypes.find(assign->var)))
+        {
+            TypeInfo ti{Pattern::Assign, toString(ctxNode), types};
+            typeInfo.push_back(ti);
+        }
+    }
+    else if (module->astTypePacks.contains(assign->var))
+    {
+        if (containsAny(*module->astTypePacks.find(assign->var)))
+        {
+            TypeInfo ti{Pattern::Assign, toString(ctxNode), types};
+            typeInfo.push_back(ti);
+        }
+    }
+
+    if (isAnyCall(scope, assign->value, module, builtinTypes))
+    {
+        TypeInfo ti{Pattern::FuncApp, toString(ctxNode), types};
+        typeInfo.push_back(ti);
+    }
+
+    if (isAnyCast(scope, assign->value, module, builtinTypes))
+    {
+        if (auto cast = assign->value->as<AstExprTypeAssertion>())
+        {
+            types.annotatedType = toString(lookupAnnotation(cast->annotation, module, builtinTypes));
+            types.inferredType = toString(lookupType(cast->expr, module, builtinTypes));
+
+            TypeInfo ti{Pattern::Casts, toString(ctxNode), types};
+            typeInfo.push_back(ti);
+        }
+    }
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatFunction* function, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    TelemetryTypePair types;
+    types.inferredType = toString(lookupType(function->func, module, builtinTypes));
+
+    if (hasVariadicAnys(scope, function->func, module, builtinTypes))
+    {
+        TypeInfo ti{Pattern::VarAny, toString(function), types};
+        typeInfo.push_back(ti);
+    }
+
+    if (hasArgAnys(scope, function->func, module, builtinTypes))
+    {
+        TypeInfo ti{Pattern::FuncArg, toString(function), types};
+        typeInfo.push_back(ti);
+    }
+
+    if (hasAnyReturns(scope, function->func, module, builtinTypes))
+    {
+        TypeInfo ti{Pattern::FuncRet, toString(function), types};
+        typeInfo.push_back(ti);
+    }
+
+    if (function->func->body->body.size > 0)
+        visit(scope, function->func->body, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatLocalFunction* function, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    TelemetryTypePair types;
+
+    if (hasVariadicAnys(scope, function->func, module, builtinTypes))
+    {
+        types.inferredType = toString(lookupType(function->func, module, builtinTypes));
+        TypeInfo ti{Pattern::VarAny, toString(function), types};
+        typeInfo.push_back(ti);
+    }
+
+    if (hasArgAnys(scope, function->func, module, builtinTypes))
+    {
+        types.inferredType = toString(lookupType(function->func, module, builtinTypes));
+        TypeInfo ti{Pattern::FuncArg, toString(function), types};
+        typeInfo.push_back(ti);
+    }
+
+    if (hasAnyReturns(scope, function->func, module, builtinTypes))
+    {
+        types.inferredType = toString(lookupType(function->func, module, builtinTypes));
+        TypeInfo ti{Pattern::FuncRet, toString(function), types};
+        typeInfo.push_back(ti);
+    }
+
+    if (function->func->body->body.size > 0)
+        visit(scope, function->func->body, module, builtinTypes);
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatTypeAlias* alias, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    auto ctxNode = getNode(rootSrc, alias);
+
+    auto annot = lookupAnnotation(alias->type, module, builtinTypes);
+    if (containsAny(annot))
+    {
+        // no expr => no inference for aliases
+        TelemetryTypePair types;
+
+        types.annotatedType = toString(annot);
+        TypeInfo ti{Pattern::Alias, toString(ctxNode), types};
+        typeInfo.push_back(ti);
+    }
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatExpr* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    auto ctxNode = getNode(rootSrc, expr);
+
+    if (isAnyCall(scope, expr->expr, module, builtinTypes))
+    {
+        TelemetryTypePair types;
+        types.inferredType = toString(lookupType(expr->expr, module, builtinTypes));
+
+        TypeInfo ti{Pattern::FuncApp, toString(ctxNode), types};
+        typeInfo.push_back(ti);
+    }
+}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatDeclareGlobal* declareGlobal, const Module* module, NotNull<BuiltinTypes> builtinTypes) {}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatDeclareClass* declareClass, const Module* module, NotNull<BuiltinTypes> builtinTypes) {}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatDeclareFunction* declareFunction, const Module* module, NotNull<BuiltinTypes> builtinTypes) {}
+
+void AnyTypeSummary::visit(const Scope* scope, AstStatError* error, const Module* module, NotNull<BuiltinTypes> builtinTypes) {}
+
+TypeId AnyTypeSummary::checkForFamilyInhabitance(const TypeId instance, const Location location)
+{
+    if (seenTypeFamilyInstances.find(instance))
+        return instance;
+
+    seenTypeFamilyInstances.insert(instance);
+    return instance;
+}
+
+TypeId AnyTypeSummary::lookupType(const AstExpr* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    const TypeId* ty = module->astTypes.find(expr);
+    if (ty)
+        return checkForFamilyInhabitance(follow(*ty), expr->location);
+
+    const TypePackId* tp = module->astTypePacks.find(expr);
+    if (tp)
+    {
+        if (auto fst = first(*tp, /*ignoreHiddenVariadics*/ false))
+            return checkForFamilyInhabitance(*fst, expr->location);
+        else if (finite(*tp) && size(*tp) == 0)
+            return checkForFamilyInhabitance(builtinTypes->nilType, expr->location);
+    }
+
+    return builtinTypes->errorRecoveryType();
+}
+
+TypePackId AnyTypeSummary::reconstructTypePack(AstArray<AstExpr*> exprs, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    if (exprs.size == 0)
+        return arena.addTypePack(TypePack{{}, std::nullopt});
+
+    std::vector<TypeId> head;
+
+    for (size_t i = 0; i < exprs.size - 1; ++i)
+    {
+        head.push_back(lookupType(exprs.data[i], module, builtinTypes));
+    }
+
+    const TypePackId* tail = module->astTypePacks.find(exprs.data[exprs.size - 1]);
+    if (tail)
+        return arena.addTypePack(TypePack{std::move(head), follow(*tail)});
+    else
+        return arena.addTypePack(TypePack{std::move(head), builtinTypes->errorRecoveryTypePack()});
+}
+
+bool AnyTypeSummary::isAnyCall(const Scope* scope, AstExpr* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    if (auto call = expr->as<AstExprCall>())
+    {
+        TypePackId args = reconstructTypePack(call->args, module, builtinTypes);
+        if (containsAny(args))
+            return true;
+
+        TypeId func = lookupType(call->func, module, builtinTypes);
+        if (containsAny(func))
+            return true;
+    }
+    return false;
+}
+
+bool AnyTypeSummary::hasVariadicAnys(const Scope* scope, AstExprFunction* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    if (expr->vararg && expr->varargAnnotation)
+    {
+        auto annot = lookupPackAnnotation(expr->varargAnnotation, module);
+        if (annot && containsAny(*annot))
+        {
+            return true;
+        }
+    }
+    return false;
+}
+
+bool AnyTypeSummary::hasArgAnys(const Scope* scope, AstExprFunction* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    if (expr->args.size > 0)
+    {
+        for (const AstLocal* arg : expr->args)
+        {
+            if (arg->annotation)
+            {
+                auto annot = lookupAnnotation(arg->annotation, module, builtinTypes);
+                if (containsAny(annot))
+                {
+                    return true;
+                }
+            }
+        }
+    }
+    return false;
+}
+
+bool AnyTypeSummary::hasAnyReturns(const Scope* scope, AstExprFunction* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    if (!expr->returnAnnotation)
+    {
+        return false;
+    }
+
+    for (AstType* ret : expr->returnAnnotation->types)
+    {
+        if (containsAny(lookupAnnotation(ret, module, builtinTypes)))
+        {
+            return true;
+        }
+    }
+
+    if (expr->returnAnnotation->tailType)
+    {
+        auto annot = lookupPackAnnotation(expr->returnAnnotation->tailType, module);
+        if (annot && containsAny(*annot))
+        {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+bool AnyTypeSummary::isAnyCast(const Scope* scope, AstExpr* expr, const Module* module, NotNull<BuiltinTypes> builtinTypes)
+{
+    if (auto cast = expr->as<AstExprTypeAssertion>())
+    {
+        auto annot = lookupAnnotation(cast->annotation, module, builtinTypes);
+        if (containsAny(annot))
+        {
+            return true;
+        }
+    }
+    return false;
+}
+
+TypeId AnyTypeSummary::lookupAnnotation(AstType* annotation, const Module* module, NotNull<BuiltinTypes> builtintypes)
+{
+    if (FFlag::DebugLuauMagicTypes)
+    {
+        if (auto ref = annotation->as<AstTypeReference>(); ref && ref->parameters.size > 0)
+        {
+            if (auto ann = ref->parameters.data[0].type)
+            {
+                TypeId argTy = lookupAnnotation(ref->parameters.data[0].type, module, builtintypes);
+                return follow(argTy);
+            }
+        }
+    }
+
+    const TypeId* ty = module->astResolvedTypes.find(annotation);
+    if (ty)
+        return checkForTypeFunctionInhabitance(follow(*ty), annotation->location);
+    else
+        return checkForTypeFunctionInhabitance(builtintypes->errorRecoveryType(), annotation->location);
+}
+
+TypeId AnyTypeSummary::checkForTypeFunctionInhabitance(const TypeId instance, const Location location)
+{
+    if (seenTypeFunctionInstances.find(instance))
+        return instance;
+    seenTypeFunctionInstances.insert(instance);
+
+    return instance;
+}
+
+std::optional<TypePackId> AnyTypeSummary::lookupPackAnnotation(AstTypePack* annotation, const Module* module)
+{
+    const TypePackId* tp = module->astResolvedTypePacks.find(annotation);
+    if (tp != nullptr)
+        return {follow(*tp)};
+    return {};
+}
+
+bool AnyTypeSummary::containsAny(TypeId typ)
+{
+    typ = follow(typ);
+
+    if (auto t = seen.find(typ); t && !*t)
+    {
+        return false;
+    }
+
+    seen[typ] = false;
+
+    RecursionCounter counter{&recursionCount};
+    if (recursionCount >= FInt::LuauAnySummaryRecursionLimit)
+    {
+        return false;
+    }
+
+    bool found = false;
+
+    if (auto ty = get<AnyType>(typ))
+    {
+        found = true;
+    }
+    else if (auto ty = get<UnknownType>(typ))
+    {
+        found = true;
+    }
+    else if (auto ty = get<TableType>(typ))
+    {
+        for (auto& [_name, prop] : ty->props)
+        {
+            if (FFlag::LuauSolverV2)
+            {
+                if (auto newT = follow(prop.readTy))
+                {
+                    if (containsAny(*newT))
+                        found = true;
+                }
+                else if (auto newT = follow(prop.writeTy))
+                {
+                    if (containsAny(*newT))
+                        found = true;
+                }
+            }
+            else
+            {
+                if (containsAny(prop.type()))
+                    found = true;
+            }
+        }
+    }
+    else if (auto ty = get<IntersectionType>(typ))
+    {
+        for (auto part : ty->parts)
+        {
+            if (containsAny(part))
+            {
+                found = true;
+            }
+        }
+    }
+    else if (auto ty = get<UnionType>(typ))
+    {
+        for (auto option : ty->options)
+        {
+            if (containsAny(option))
+            {
+                found = true;
+            }
+        }
+    }
+    else if (auto ty = get<FunctionType>(typ))
+    {
+        if (containsAny(ty->argTypes))
+            found = true;
+        else if (containsAny(ty->retTypes))
+            found = true;
+    }
+
+    seen[typ] = found;
+
+    return found;
+}
+
+bool AnyTypeSummary::containsAny(TypePackId typ)
+{
+    typ = follow(typ);
+
+    if (auto t = seen.find(typ); t && !*t)
+    {
+        return false;
+    }
+
+    seen[typ] = false;
+
+    auto [head, tail] = flatten(typ);
+    bool found = false;
+
+    for (auto tp : head)
+    {
+        if (containsAny(tp))
+            found = true;
+    }
+
+    if (tail)
+    {
+        if (auto vtp = get<VariadicTypePack>(tail))
+        {
+            if (auto ty = get<AnyType>(follow(vtp->ty)))
+            {
+                found = true;
+            }
+        }
+        else if (auto tftp = get<TypeFunctionInstanceTypePack>(tail))
+        {
+
+            for (TypePackId tp : tftp->packArguments)
+            {
+                if (containsAny(tp))
+                {
+                    found = true;
+                }
+            }
+
+            for (TypeId t : tftp->typeArguments)
+            {
+                if (containsAny(t))
+                {
+                    found = true;
+                }
+            }
+        }
+    }
+
+    seen[typ] = found;
+
+    return found;
+}
+
+const Scope* AnyTypeSummary::findInnerMostScope(const Location location, const Module* module)
+{
+    const Scope* bestScope = module->getModuleScope().get();
+
+    bool didNarrow = false;
+    do
+    {
+        didNarrow = false;
+        for (auto scope : bestScope->children)
+        {
+            if (scope->location.encloses(location))
+            {
+                bestScope = scope.get();
+                didNarrow = true;
+                break;
+            }
+        }
+    } while (didNarrow && bestScope->children.size() > 0);
+
+    return bestScope;
+}
+
+std::optional<AstExpr*> AnyTypeSummary::matchRequire(const AstExprCall& call)
+{
+    const char* require = "require";
+
+    if (call.args.size != 1)
+        return std::nullopt;
+
+    const AstExprGlobal* funcAsGlobal = call.func->as<AstExprGlobal>();
+    if (!funcAsGlobal || funcAsGlobal->name != require)
+        return std::nullopt;
+
+    if (call.args.size != 1)
+        return std::nullopt;
+
+    return call.args.data[0];
+}
+
+AstNode* AnyTypeSummary::getNode(AstStatBlock* root, AstNode* node)
+{
+    FindReturnAncestry finder(node, root->location.end);
+    root->visit(&finder);
+
+    if (!finder.currNode)
+        finder.currNode = node;
+
+    LUAU_ASSERT(finder.found && finder.currNode);
+    return finder.currNode;
+}
+
+bool AnyTypeSummary::FindReturnAncestry::visit(AstStatLocalFunction* node)
+{
+    currNode = node;
+    return !found;
+}
+
+bool AnyTypeSummary::FindReturnAncestry::visit(AstStatFunction* node)
+{
+    currNode = node;
+    return !found;
+}
+
+bool AnyTypeSummary::FindReturnAncestry::visit(AstType* node)
+{
+    return !found;
+}
+
+bool AnyTypeSummary::FindReturnAncestry::visit(AstNode* node)
+{
+    if (node == stat)
+    {
+        found = true;
+    }
+
+    if (node->location.end == rootEnd && stat->location.end >= rootEnd)
+    {
+        currNode = node;
+        found = true;
+    }
+
+    return !found;
+}
+
+
+AnyTypeSummary::TypeInfo::TypeInfo(Pattern code, std::string node, TelemetryTypePair type)
+    : code(code)
+    , node(node)
+    , type(type)
+{
+}
+
+AnyTypeSummary::FindReturnAncestry::FindReturnAncestry(AstNode* stat, Position rootEnd)
+    : stat(stat)
+    , rootEnd(rootEnd)
+{
+}
+
+AnyTypeSummary::AnyTypeSummary() {}
+
+} // namespace Luau
--- a/Analysis/src/Anyification.cpp
+++ b/Analysis/src/Anyification.cpp
@ -88,7 +88,7 @@ TypePackId Anyification::clean(TypePackId tp)

 bool Anyification::ignoreChildren(TypeId ty)
 {
-    if (get<ExternType>(ty))
+    if (get<ClassType>(ty))
        return true;

    return ty->persistent;
--- a/Analysis/src/ApplyTypeFunction.cpp
+++ b/Analysis/src/ApplyTypeFunction.cpp
@ -31,7 +31,7 @@ bool ApplyTypeFunction::ignoreChildren(TypeId ty)
 {
    if (get<GenericType>(ty))
        return true;
-    else if (get<ExternType>(ty))
+    else if (get<ClassType>(ty))
        return true;
    else
        return false;
--- a/Analysis/src/AstJsonEncoder.cpp
+++ b/Analysis/src/AstJsonEncoder.cpp
@ -8,8 +8,6 @@

 #include <math.h>

-LUAU_FASTFLAG(LuauStoreReturnTypesAsPackOnAst)
-
 namespace Luau
 {

@ -433,16 +431,8 @@ struct AstJsonEncoder : public AstVisitor
                if (node->self)
                    PROP(self);
                PROP(args);
-                if (FFlag::LuauStoreReturnTypesAsPackOnAst)
-                {
-                    if (node->returnAnnotation)
-                        PROP(returnAnnotation);
-                }
-                else
-                {
-                    if (node->returnAnnotation_DEPRECATED)
-                        write("returnAnnotation", node->returnAnnotation_DEPRECATED);
-                }
+                if (node->returnAnnotation)
+                    PROP(returnAnnotation);
                PROP(vararg);
                PROP(varargLocation);
                if (node->varargAnnotation)
@ -475,26 +465,26 @@ struct AstJsonEncoder : public AstVisitor
        writeRaw("}");
    }

-    void write(class AstGenericType* genericType)
+    void write(const AstGenericType& genericType)
    {
        writeRaw("{");
        bool c = pushComma();
        writeType("AstGenericType");
-        write("name", genericType->name);
-        if (genericType->defaultValue)
-            write("luauType", genericType->defaultValue);
+        write("name", genericType.name);
+        if (genericType.defaultValue)
+            write("luauType", genericType.defaultValue);
        popComma(c);
        writeRaw("}");
    }

-    void write(class AstGenericTypePack* genericTypePack)
+    void write(const AstGenericTypePack& genericTypePack)
    {
        writeRaw("{");
        bool c = pushComma();
        writeType("AstGenericTypePack");
-        write("name", genericTypePack->name);
-        if (genericTypePack->defaultValue)
-            write("luauType", genericTypePack->defaultValue);
+        write("name", genericTypePack.name);
+        if (genericTypePack.defaultValue)
+            write("luauType", genericTypePack.defaultValue);
        popComma(c);
        writeRaw("}");
    }
@ -912,10 +902,7 @@ struct AstJsonEncoder : public AstVisitor
                PROP(paramNames);
                PROP(vararg);
                PROP(varargLocation);
-                if (FFlag::LuauStoreReturnTypesAsPackOnAst)
-                    PROP(retTypes);
-                else
-                    write("retTypes", node->retTypes_DEPRECATED);
+                PROP(retTypes);
                PROP(generics);
                PROP(genericPacks);
            }
@ -936,7 +923,7 @@ struct AstJsonEncoder : public AstVisitor
        );
    }

-    void write(const AstDeclaredExternTypeProperty& prop)
+    void write(const AstDeclaredClassProp& prop)
    {
        writeRaw("{");
        bool c = pushComma();
@ -949,7 +936,7 @@ struct AstJsonEncoder : public AstVisitor
        writeRaw("}");
    }

-    void write(class AstStatDeclareExternType* node)
+    void write(class AstStatDeclareClass* node)
    {
        writeNode(
            node,
@ -1061,10 +1048,7 @@ struct AstJsonEncoder : public AstVisitor
                PROP(genericPacks);
                PROP(argTypes);
                PROP(argNames);
-                if (FFlag::LuauStoreReturnTypesAsPackOnAst)
-                    PROP(returnTypes);
-                else
-                    write("returnTypes", node->returnTypes_DEPRECATED);
+                PROP(returnTypes);
            }
        );
    }
@ -1081,11 +1065,6 @@ struct AstJsonEncoder : public AstVisitor
        );
    }

-    void write(class AstTypeOptional* node)
-    {
-        writeNode(node, "AstTypeOptional", [&]() {});
-    }
-
    void write(class AstTypeUnion* node)
    {
        writeNode(
@ -1167,8 +1146,6 @@ struct AstJsonEncoder : public AstVisitor
            return writeString("checked");
        case AstAttr::Type::Native:
            return writeString("native");
-        case AstAttr::Type::Deprecated:
-            return writeString("deprecated");
        }
    }

@ -1184,19 +1161,6 @@ struct AstJsonEncoder : public AstVisitor
        );
    }

-    bool visit(class AstTypeGroup* node) override
-    {
-        writeNode(
-            node,
-            "AstTypeGroup",
-            [&]()
-            {
-                write("inner", node->type);
-            }
-        );
-        return false;
-    }
-
    bool visit(class AstTypeSingletonBool* node) override
    {
        writeNode(
@ -1445,7 +1409,7 @@ struct AstJsonEncoder : public AstVisitor
        return false;
    }

-    bool visit(class AstStatDeclareExternType* node) override
+    bool visit(class AstStatDeclareClass* node) override
    {
        write(node);
        return false;
--- a/Analysis/src/AstQuery.cpp
+++ b/Analysis/src/AstQuery.cpp
@ -13,6 +13,8 @@

 LUAU_FASTFLAG(LuauSolverV2)

+LUAU_FASTFLAG(LuauExtendStatEndPosWithSemicolon)
+
 namespace Luau
 {

@ -41,13 +43,24 @@ struct AutocompleteNodeFinder : public AstVisitor

    bool visit(AstStat* stat) override
    {
-        // Consider 'local myLocal = 4;|' and 'local myLocal = 4', where '|' is the cursor position. In both cases, the cursor position is equal
-        // to `AstStatLocal.location.end`. However, in the first case (semicolon), we are starting a new statement, whilst in the second case
-        // (no semicolon) we are still part of the AstStatLocal, hence the different comparison check.
-        if (stat->location.begin < pos && (stat->hasSemicolon ? pos < stat->location.end : pos <= stat->location.end))
+        if (FFlag::LuauExtendStatEndPosWithSemicolon)
        {
-            ancestry.push_back(stat);
-            return true;
+            // Consider 'local myLocal = 4;|' and 'local myLocal = 4', where '|' is the cursor position. In both cases, the cursor position is equal
+            // to `AstStatLocal.location.end`. However, in the first case (semicolon), we are starting a new statement, whilst in the second case
+            // (no semicolon) we are still part of the AstStatLocal, hence the different comparison check.
+            if (stat->location.begin < pos && (stat->hasSemicolon ? pos < stat->location.end : pos <= stat->location.end))
+            {
+                ancestry.push_back(stat);
+                return true;
+            }
+        }
+        else
+        {
+            if (stat->location.begin < pos && pos <= stat->location.end)
+            {
+                ancestry.push_back(stat);
+                return true;
+            }
        }

        return false;
@ -574,11 +587,11 @@ std::optional<DocumentationSymbol> getDocumentationSymbolAtPosition(const Source
                            return checkOverloadedDocumentationSymbol(module, propIt->second.type(), parentExpr, propIt->second.documentationSymbol);
                    }
                }
-                else if (const ExternType* etv = get<ExternType>(parentTy))
+                else if (const ClassType* ctv = get<ClassType>(parentTy))
                {
-                    while (etv)
+                    while (ctv)
                    {
-                        if (auto propIt = etv->props.find(indexName->index.value); propIt != etv->props.end())
+                        if (auto propIt = ctv->props.find(indexName->index.value); propIt != ctv->props.end())
                        {
                            if (FFlag::LuauSolverV2)
                            {
@ -590,7 +603,7 @@ std::optional<DocumentationSymbol> getDocumentationSymbolAtPosition(const Source
                                    module, propIt->second.type(), parentExpr, propIt->second.documentationSymbol
                                );
                        }
-                        etv = etv->parent ? Luau::get<Luau::ExternType>(*etv->parent) : nullptr;
+                        ctv = ctv->parent ? Luau::get<Luau::ClassType>(*ctv->parent) : nullptr;
                    }
                }
                else if (const PrimitiveType* ptv = get<PrimitiveType>(parentTy); ptv && ptv->metatable)
--- a/Analysis/src/Autocomplete.cpp
+++ b/Analysis/src/Autocomplete.cpp
@ -2,7 +2,6 @@
 #include "Luau/Autocomplete.h"

 #include "Luau/AstQuery.h"
-#include "Luau/TimeTrace.h"
 #include "Luau/TypeArena.h"
 #include "Luau/Module.h"
 #include "Luau/Frontend.h"
@ -16,9 +15,6 @@ namespace Luau

 AutocompleteResult autocomplete(Frontend& frontend, const ModuleName& moduleName, Position position, StringCompletionCallback callback)
 {
-    LUAU_TIMETRACE_SCOPE("Luau::autocomplete", "Autocomplete");
-    LUAU_TIMETRACE_ARGUMENT("name", moduleName.c_str());
-
    const SourceModule* sourceModule = frontend.getSourceModule(moduleName);
    if (!sourceModule)
        return {};
--- a/Analysis/src/AutocompleteCore.cpp
+++ b/Analysis/src/AutocompleteCore.cpp
@ -10,7 +10,6 @@
 #include "Luau/Common.h"
 #include "Luau/FileResolver.h"
 #include "Luau/Frontend.h"
-#include "Luau/TimeTrace.h"
 #include "Luau/ToString.h"
 #include "Luau/Subtyping.h"
 #include "Luau/TypeInfer.h"
@ -21,13 +20,12 @@
 #include <utility>

 LUAU_FASTFLAG(LuauSolverV2)
+LUAU_FASTFLAGVARIABLE(AutocompleteRequirePathSuggestions2)
 LUAU_FASTINT(LuauTypeInferIterationLimit)
 LUAU_FASTINT(LuauTypeInferRecursionLimit)
-LUAU_FASTFLAGVARIABLE(DebugLuauMagicVariableNames)
-LUAU_FASTFLAGVARIABLE(LuauAutocompleteUsesModuleForTypeCompatibility)
-LUAU_FASTFLAGVARIABLE(LuauAutocompleteUnionCopyPreviousSeen)
-LUAU_FASTFLAGVARIABLE(LuauAutocompleteMissingFollows)
-LUAU_FASTFLAG(LuauStoreReturnTypesAsPackOnAst)
+
+LUAU_FASTFLAGVARIABLE(LuauAutocompleteRefactorsForIncrementalAutocomplete)
+LUAU_FASTFLAGVARIABLE(LuauAutocompleteUseLimits)

 static const std::unordered_set<std::string> kStatementStartingKeywords =
    {"while", "if", "local", "repeat", "function", "do", "for", "return", "break", "continue", "type", "export"};
@ -80,8 +78,6 @@ static ParenthesesRecommendation getParenRecommendationForIntersect(const Inters
    ParenthesesRecommendation rec = ParenthesesRecommendation::None;
    for (Luau::TypeId partId : intersect->parts)
    {
-        if (FFlag::LuauAutocompleteMissingFollows)
-            partId = follow(partId);
        if (auto partFunc = Luau::get<FunctionType>(partId))
        {
            rec = std::max(rec, getParenRecommendationForFunc(partFunc, nodes));
@ -151,91 +147,44 @@ static std::optional<TypeId> findExpectedTypeAt(const Module& module, AstNode* n
    return *it;
 }

-static bool checkTypeMatch(
-    const Module& module,
-    TypeId subTy,
-    TypeId superTy,
-    NotNull<Scope> scope,
-    TypeArena* typeArena,
-    NotNull<BuiltinTypes> builtinTypes
-)
+static bool checkTypeMatch(TypeId subTy, TypeId superTy, NotNull<Scope> scope, TypeArena* typeArena, NotNull<BuiltinTypes> builtinTypes)
 {
    InternalErrorReporter iceReporter;
    UnifierSharedState unifierState(&iceReporter);
    SimplifierPtr simplifier = newSimplifier(NotNull{typeArena}, builtinTypes);
    Normalizer normalizer{typeArena, builtinTypes, NotNull{&unifierState}};
-    if (FFlag::LuauAutocompleteUsesModuleForTypeCompatibility)
+
+    if (FFlag::LuauSolverV2)
    {
-        if (module.checkedInNewSolver)
-        {
-            TypeCheckLimits limits;
-            TypeFunctionRuntime typeFunctionRuntime{
-                NotNull{&iceReporter}, NotNull{&limits}
-            }; // TODO: maybe subtyping checks should not invoke user-defined type function runtime
+        TypeCheckLimits limits;
+        TypeFunctionRuntime typeFunctionRuntime{
+            NotNull{&iceReporter}, NotNull{&limits}
+        }; // TODO: maybe subtyping checks should not invoke user-defined type function runtime

-            unifierState.counters.recursionLimit = FInt::LuauTypeInferRecursionLimit;
-            unifierState.counters.iterationLimit = FInt::LuauTypeInferIterationLimit;
+        unifierState.counters.recursionLimit = FInt::LuauTypeInferRecursionLimit;
+        unifierState.counters.iterationLimit = FInt::LuauTypeInferIterationLimit;

-            Subtyping subtyping{
-                builtinTypes,
-                NotNull{typeArena},
-                NotNull{simplifier.get()},
-                NotNull{&normalizer},
-                NotNull{&typeFunctionRuntime},
-                NotNull{&iceReporter}
-            };
+        Subtyping subtyping{
+            builtinTypes, NotNull{typeArena}, NotNull{simplifier.get()}, NotNull{&normalizer}, NotNull{&typeFunctionRuntime}, NotNull{&iceReporter}
+        };

-            return subtyping.isSubtype(subTy, superTy, scope).isSubtype;
-        }
-        else
-        {
-            Unifier unifier(NotNull<Normalizer>{&normalizer}, scope, Location(), Variance::Covariant);
-
-            // Cost of normalization can be too high for autocomplete response time requirements
-            unifier.normalize = false;
-            unifier.checkInhabited = false;
-
-            unifierState.counters.recursionLimit = FInt::LuauTypeInferRecursionLimit;
-            unifierState.counters.iterationLimit = FInt::LuauTypeInferIterationLimit;
-
-            return unifier.canUnify(subTy, superTy).empty();
-        }
+        return subtyping.isSubtype(subTy, superTy, scope).isSubtype;
    }
    else
    {
-        if (FFlag::LuauSolverV2)
-        {
-            TypeCheckLimits limits;
-            TypeFunctionRuntime typeFunctionRuntime{
-                NotNull{&iceReporter}, NotNull{&limits}
-            }; // TODO: maybe subtyping checks should not invoke user-defined type function runtime
+        Unifier unifier(NotNull<Normalizer>{&normalizer}, scope, Location(), Variance::Covariant);

+        // Cost of normalization can be too high for autocomplete response time requirements
+        unifier.normalize = false;
+        unifier.checkInhabited = false;
+
+        if (FFlag::LuauAutocompleteUseLimits)
+        {
            unifierState.counters.recursionLimit = FInt::LuauTypeInferRecursionLimit;
            unifierState.counters.iterationLimit = FInt::LuauTypeInferIterationLimit;
-
-            Subtyping subtyping{
-                builtinTypes,
-                NotNull{typeArena},
-                NotNull{simplifier.get()},
-                NotNull{&normalizer},
-                NotNull{&typeFunctionRuntime},
-                NotNull{&iceReporter}
-            };
-
-            return subtyping.isSubtype(subTy, superTy, scope).isSubtype;
        }
-        else
-        {
-            Unifier unifier(NotNull<Normalizer>{&normalizer}, scope, Location(), Variance::Covariant);

-            // Cost of normalization can be too high for autocomplete response time requirements
-            unifier.normalize = false;
-            unifier.checkInhabited = false;
-            unifierState.counters.recursionLimit = FInt::LuauTypeInferRecursionLimit;
-            unifierState.counters.iterationLimit = FInt::LuauTypeInferIterationLimit;
-
-            return unifier.canUnify(subTy, superTy).empty();
-        }
+        return unifier.canUnify(subTy, superTy).empty();
    }
 }

@ -261,10 +210,10 @@ static TypeCorrectKind checkTypeCorrectKind(

    TypeId expectedType = follow(*typeAtPosition);

-    auto checkFunctionType = [typeArena, builtinTypes, moduleScope, &expectedType, &module](const FunctionType* ftv)
+    auto checkFunctionType = [typeArena, builtinTypes, moduleScope, &expectedType](const FunctionType* ftv)
    {
        if (std::optional<TypeId> firstRetTy = first(ftv->retTypes))
-            return checkTypeMatch(module, *firstRetTy, expectedType, moduleScope, typeArena, builtinTypes);
+            return checkTypeMatch(*firstRetTy, expectedType, moduleScope, typeArena, builtinTypes);

        return false;
    };
@ -287,7 +236,7 @@ static TypeCorrectKind checkTypeCorrectKind(
        }
    }

-    return checkTypeMatch(module, ty, expectedType, moduleScope, typeArena, builtinTypes) ? TypeCorrectKind::Correct : TypeCorrectKind::None;
+    return checkTypeMatch(ty, expectedType, moduleScope, typeArena, builtinTypes) ? TypeCorrectKind::Correct : TypeCorrectKind::None;
 }

 enum class PropIndexType
@ -307,7 +256,7 @@ static void autocompleteProps(
    const std::vector<AstNode*>& nodes,
    AutocompleteEntryMap& result,
    std::unordered_set<TypeId>& seen,
-    std::optional<const ExternType*> containingExternType = std::nullopt
+    std::optional<const ClassType*> containingClass = std::nullopt
 )
 {
    rootTy = follow(rootTy);
@ -330,15 +279,15 @@ static void autocompleteProps(
            if (calledWithSelf == ftv->hasSelf)
                return true;

-            // Calls on extern types require strict match between how function is declared and how it's called
-            if (get<ExternType>(rootTy))
+            // Calls on classes require strict match between how function is declared and how it's called
+            if (get<ClassType>(rootTy))
                return false;

            // When called with ':', but declared without 'self', it is invalid if a function has incompatible first argument or no arguments at all
            // When called with '.', but declared with 'self', it is considered invalid if first argument is compatible
            if (std::optional<TypeId> firstArgTy = first(ftv->argTypes))
            {
-                if (checkTypeMatch(module, rootTy, *firstArgTy, NotNull{module.getModuleScope().get()}, typeArena, builtinTypes))
+                if (checkTypeMatch(rootTy, *firstArgTy, NotNull{module.getModuleScope().get()}, typeArena, builtinTypes))
                    return calledWithSelf;
            }

@ -364,7 +313,7 @@ static void autocompleteProps(
        return calledWithSelf;
    };

-    auto fillProps = [&](const ExternType::Props& props)
+    auto fillProps = [&](const ClassType::Props& props)
    {
        for (const auto& [name, prop] : props)
        {
@ -397,7 +346,7 @@ static void autocompleteProps(
                    prop.deprecated,
                    isWrongIndexer(type),
                    typeCorrect,
-                    containingExternType,
+                    containingClass,
                    &prop,
                    prop.documentationSymbol,
                    {},
@ -428,12 +377,12 @@ static void autocompleteProps(
        }
    };

-    if (auto cls = get<ExternType>(ty))
+    if (auto cls = get<ClassType>(ty))
    {
-        containingExternType = containingExternType.value_or(cls);
+        containingClass = containingClass.value_or(cls);
        fillProps(cls->props);
        if (cls->parent)
-            autocompleteProps(module, typeArena, builtinTypes, rootTy, *cls->parent, indexType, nodes, result, seen, containingExternType);
+            autocompleteProps(module, typeArena, builtinTypes, rootTy, *cls->parent, indexType, nodes, result, seen, containingClass);
    }
    else if (auto tbl = get<TableType>(ty))
        fillProps(tbl->props);
@ -484,21 +433,6 @@ static void autocompleteProps(
            AutocompleteEntryMap inner;
            std::unordered_set<TypeId> innerSeen;

-            // If we don't do this, and we have the misfortune of receiving a
-            // recursive union like:
-            //
-            //  t1 where t1 = t1 | ExternType
-            //
-            // Then we are on a one way journey to a stack overflow.
-            if (FFlag::LuauAutocompleteUnionCopyPreviousSeen)
-            {
-                for (auto ty : seen)
-                {
-                    if (is<UnionType, IntersectionType>(ty))
-                        innerSeen.insert(ty);
-                }
-            }
-
            if (isNil(*iter))
            {
                ++iter;
@ -587,7 +521,7 @@ AutocompleteEntryMap autocompleteProps(
 AutocompleteEntryMap autocompleteModuleTypes(const Module& module, const ScopePtr& scopeAtPosition, Position position, std::string_view moduleName)
 {
    AutocompleteEntryMap result;
-    ScopePtr startScope = scopeAtPosition;
+    ScopePtr startScope = FFlag::LuauAutocompleteRefactorsForIncrementalAutocomplete ? scopeAtPosition : findScopeAtPosition(module, position);
    for (ScopePtr& scope = startScope; scope; scope = scope->parent)
    {
        if (auto it = scope->importedTypeBindings.find(std::string(moduleName)); it != scope->importedTypeBindings.end())
@ -699,30 +633,6 @@ static std::optional<TypeId> findTypeElementAt(const AstTypeList& astTypeList, T
    return {};
 }

-static std::optional<TypeId> findTypeElementAt(AstTypePack* astTypePack, TypePackId tp, Position position)
-{
-    LUAU_ASSERT(FFlag::LuauStoreReturnTypesAsPackOnAst);
-    if (const auto typePack = astTypePack->as<AstTypePackExplicit>())
-    {
-        return findTypeElementAt(typePack->typeList, tp, position);
-    }
-    else if (const auto variadic = astTypePack->as<AstTypePackVariadic>())
-    {
-        if (variadic->location.containsClosed(position))
-        {
-            auto [_, tail] = flatten(tp);
-
-            if (tail)
-            {
-                if (const VariadicTypePack* vtp = get<VariadicTypePack>(follow(*tail)))
-                    return findTypeElementAt(variadic->variadicType, vtp->ty, position);
-            }
-        }
-    }
-
-    return {};
-}
-
 static std::optional<TypeId> findTypeElementAt(AstType* astType, TypeId ty, Position position)
 {
    ty = follow(ty);
@ -743,16 +653,8 @@ static std::optional<TypeId> findTypeElementAt(AstType* astType, TypeId ty, Posi
        if (auto element = findTypeElementAt(type->argTypes, ftv->argTypes, position))
            return element;

-        if (FFlag::LuauStoreReturnTypesAsPackOnAst)
-        {
-            if (auto element = findTypeElementAt(type->returnTypes, ftv->retTypes, position))
-                return element;
-        }
-        else
-        {
-            if (auto element = findTypeElementAt(type->returnTypes_DEPRECATED, ftv->retTypes, position))
-                return element;
-        }
+        if (auto element = findTypeElementAt(type->returnTypes, ftv->retTypes, position))
+            return element;
    }

    // It's possible to walk through other types like intrsection and unions if we find value in doing that
@ -761,7 +663,7 @@ static std::optional<TypeId> findTypeElementAt(AstType* astType, TypeId ty, Posi

 std::optional<TypeId> getLocalTypeInScopeAt(const Module& module, const ScopePtr& scopeAtPosition, Position position, AstLocal* local)
 {
-    if (ScopePtr scope = scopeAtPosition)
+    if (ScopePtr scope = FFlag::LuauAutocompleteRefactorsForIncrementalAutocomplete ? scopeAtPosition : findScopeAtPosition(module, position))
    {
        for (const auto& [name, binding] : scope->bindings)
        {
@ -903,7 +805,7 @@ AutocompleteEntryMap autocompleteTypeNames(
 {
    AutocompleteEntryMap result;

-    ScopePtr startScope = scopeAtPosition;
+    ScopePtr startScope = FFlag::LuauAutocompleteRefactorsForIncrementalAutocomplete ? scopeAtPosition : findScopeAtPosition(module, position);

    for (ScopePtr scope = startScope; scope; scope = scope->parent)
    {
@ -1082,46 +984,29 @@ AutocompleteEntryMap autocompleteTypeNames(
            }
        }

-        if (FFlag::LuauStoreReturnTypesAsPackOnAst)
+        if (!node->returnAnnotation)
+            return result;
+
+        for (size_t i = 0; i < node->returnAnnotation->types.size; i++)
        {
-            if (!node->returnAnnotation)
-                return result;
+            AstType* ret = node->returnAnnotation->types.data[i];

-            if (const auto typePack = node->returnAnnotation->as<AstTypePackExplicit>())
+            if (ret->location.containsClosed(position))
            {
-                for (size_t i = 0; i < typePack->typeList.types.size; i++)
+                if (const FunctionType* ftv = tryGetExpectedFunctionType(module, node))
                {
-                    AstType* ret = typePack->typeList.types.data[i];
-
-                    if (ret->location.containsClosed(position))
-                    {
-                        if (const FunctionType* ftv = tryGetExpectedFunctionType(module, node))
-                        {
-                            if (auto ty = tryGetTypePackTypeAt(ftv->retTypes, i))
-                                tryAddTypeCorrectSuggestion(result, startScope, topType, *ty, position);
-                        }
-
-                        // TODO: with additional type information, we could suggest inferred return type here
-                        break;
-                    }
+                    if (auto ty = tryGetTypePackTypeAt(ftv->retTypes, i))
+                        tryAddTypeCorrectSuggestion(result, startScope, topType, *ty, position);
                }

-                if (AstTypePack* retTp = typePack->typeList.tailType)
-                {
-                    if (auto variadic = retTp->as<AstTypePackVariadic>())
-                    {
-                        if (variadic->location.containsClosed(position))
-                        {
-                            if (const FunctionType* ftv = tryGetExpectedFunctionType(module, node))
-                            {
-                                if (auto ty = tryGetTypePackTypeAt(ftv->retTypes, ~0u))
-                                    tryAddTypeCorrectSuggestion(result, startScope, topType, *ty, position);
-                            }
-                        }
-                    }
-                }
+                // TODO: with additional type information, we could suggest inferred return type here
+                break;
            }
-            else if (auto variadic = node->returnAnnotation->as<AstTypePackVariadic>())
+        }
+
+        if (AstTypePack* retTp = node->returnAnnotation->tailType)
+        {
+            if (auto variadic = retTp->as<AstTypePackVariadic>())
            {
                if (variadic->location.containsClosed(position))
                {
@ -1133,43 +1018,6 @@ AutocompleteEntryMap autocompleteTypeNames(
                }
            }
        }
-        else
-        {
-            if (!node->returnAnnotation_DEPRECATED)
-                return result;
-
-            for (size_t i = 0; i < node->returnAnnotation_DEPRECATED->types.size; i++)
-            {
-                AstType* ret = node->returnAnnotation_DEPRECATED->types.data[i];
-
-                if (ret->location.containsClosed(position))
-                {
-                    if (const FunctionType* ftv = tryGetExpectedFunctionType(module, node))
-                    {
-                        if (auto ty = tryGetTypePackTypeAt(ftv->retTypes, i))
-                            tryAddTypeCorrectSuggestion(result, startScope, topType, *ty, position);
-                    }
-
-                    // TODO: with additional type information, we could suggest inferred return type here
-                    break;
-                }
-            }
-
-            if (AstTypePack* retTp = node->returnAnnotation_DEPRECATED->tailType)
-            {
-                if (auto variadic = retTp->as<AstTypePackVariadic>())
-                {
-                    if (variadic->location.containsClosed(position))
-                    {
-                        if (const FunctionType* ftv = tryGetExpectedFunctionType(module, node))
-                        {
-                            if (auto ty = tryGetTypePackTypeAt(ftv->retTypes, ~0u))
-                                tryAddTypeCorrectSuggestion(result, startScope, topType, *ty, position);
-                        }
-                    }
-                }
-            }
-        }
    }

    return result;
@ -1290,7 +1138,7 @@ static AutocompleteEntryMap autocompleteStatement(
 )
 {
    // This is inefficient. :(
-    ScopePtr scope = scopeAtPosition;
+    ScopePtr scope = FFlag::LuauAutocompleteRefactorsForIncrementalAutocomplete ? scopeAtPosition : findScopeAtPosition(module, position);

    AutocompleteEntryMap result;

@ -1447,15 +1295,6 @@ static AutocompleteContext autocompleteExpression(

    AstNode* node = ancestry.rbegin()[0];

-    if (FFlag::DebugLuauMagicVariableNames)
-    {
-        InternalErrorReporter ice;
-        if (auto local = node->as<AstExprLocal>(); local && local->local->name == "_luau_autocomplete_ice")
-            ice.ice("_luau_autocomplete_ice encountered", local->location);
-        if (auto global = node->as<AstExprGlobal>(); global && global->name == "_luau_autocomplete_ice")
-            ice.ice("_luau_autocomplete_ice encountered", global->location);
-    }
-
    if (node->is<AstExprIndexName>())
    {
        if (auto it = module.astTypes.find(node->asExpr()))
@ -1468,7 +1307,7 @@ static AutocompleteContext autocompleteExpression(
    else
    {
        // This is inefficient. :(
-        ScopePtr scope = scopeAtPosition;
+        ScopePtr scope = FFlag::LuauAutocompleteRefactorsForIncrementalAutocomplete ? scopeAtPosition : findScopeAtPosition(module, position);

        while (scope)
        {
@ -1537,7 +1376,7 @@ static AutocompleteResult autocompleteExpression(
    return {result, ancestry, context};
 }

-static std::optional<const ExternType*> getMethodContainingExternType(const ModulePtr& module, AstExpr* funcExpr)
+static std::optional<const ClassType*> getMethodContainingClass(const ModulePtr& module, AstExpr* funcExpr)
 {
    AstExpr* parentExpr = nullptr;
    if (auto indexName = funcExpr->as<AstExprIndexName>())
@ -1561,14 +1400,14 @@ static std::optional<const ExternType*> getMethodContainingExternType(const Modu

    Luau::TypeId parentType = Luau::follow(*parentIt);

-    if (auto parentExternType = Luau::get<ExternType>(parentType))
+    if (auto parentClass = Luau::get<ClassType>(parentType))
    {
-        return parentExternType;
+        return parentClass;
    }

    if (auto parentUnion = Luau::get<UnionType>(parentType))
    {
-        return returnFirstNonnullOptionOfType<ExternType>(parentUnion);
+        return returnFirstNonnullOptionOfType<ClassType>(parentUnion);
    }

    return std::nullopt;
@ -1622,11 +1461,10 @@ static std::optional<AutocompleteEntryMap> convertRequireSuggestionsToAutocomple
        return std::nullopt;

    AutocompleteEntryMap result;
-    for (RequireSuggestion& suggestion : *suggestions)
+    for (const RequireSuggestion& suggestion : *suggestions)
    {
        AutocompleteEntry entry = {AutocompleteEntryKind::RequirePath};
        entry.insertText = std::move(suggestion.fullPath);
-        entry.tags = std::move(suggestion.tags);
        result[std::move(suggestion.label)] = std::move(entry);
    }
    return result;
@ -1683,11 +1521,14 @@ static std::optional<AutocompleteEntryMap> autocompleteStringParams(
    {
        for (const std::string& tag : funcType->tags)
        {
-            if (tag == kRequireTagName && fileResolver)
+            if (FFlag::AutocompleteRequirePathSuggestions2)
            {
-                return convertRequireSuggestionsToAutocompleteEntryMap(fileResolver->getRequireSuggestions(module->name, candidateString));
+                if (tag == kRequireTagName && fileResolver)
+                {
+                    return convertRequireSuggestionsToAutocompleteEntryMap(fileResolver->getRequireSuggestions(module->name, candidateString));
+                }
            }
-            if (std::optional<AutocompleteEntryMap> ret = callback(tag, getMethodContainingExternType(module, candidate->func), candidateString))
+            if (std::optional<AutocompleteEntryMap> ret = callback(tag, getMethodContainingClass(module, candidate->func), candidateString))
            {
                return ret;
            }
@ -1705,8 +1546,6 @@ static std::optional<AutocompleteEntryMap> autocompleteStringParams(
    {
        for (TypeId part : intersect->parts)
        {
-            if (FFlag::LuauAutocompleteMissingFollows)
-                part = follow(part);
            if (auto candidateFunctionType = Luau::get<FunctionType>(part))
            {
                if (std::optional<AutocompleteEntryMap> ret = performCallback(candidateFunctionType))
@ -1855,7 +1694,7 @@ static std::optional<AutocompleteEntry> makeAnonymousAutofilled(
    if (!type)
        return std::nullopt;

-    const ScopePtr scope = scopeAtPosition;
+    const ScopePtr scope = FFlag::LuauAutocompleteRefactorsForIncrementalAutocomplete ? scopeAtPosition : findScopeAtPosition(*module, position);
    if (!scope)
        return std::nullopt;

@ -1879,7 +1718,6 @@ AutocompleteResult autocomplete_(
    StringCompletionCallback callback
 )
 {
-    LUAU_TIMETRACE_SCOPE("Luau::autocomplete_", "AutocompleteCore");
    AstNode* node = ancestry.back();

    AstExprConstantNil dummy{Location{}};
--- a/Analysis/src/BuiltinDefinitions.cpp
+++ b/Analysis/src/BuiltinDefinitions.cpp
@ -3,23 +3,22 @@

 #include "Luau/Ast.h"
 #include "Luau/Clone.h"
-#include "Luau/Common.h"
-#include "Luau/ConstraintGenerator.h"
-#include "Luau/ConstraintSolver.h"
 #include "Luau/DenseHash.h"
 #include "Luau/Error.h"
 #include "Luau/Frontend.h"
-#include "Luau/InferPolarity.h"
-#include "Luau/NotNull.h"
-#include "Luau/Subtyping.h"
 #include "Luau/Symbol.h"
+#include "Luau/Common.h"
 #include "Luau/ToString.h"
-#include "Luau/Type.h"
+#include "Luau/ConstraintSolver.h"
+#include "Luau/ConstraintGenerator.h"
+#include "Luau/NotNull.h"
+#include "Luau/TypeInfer.h"
 #include "Luau/TypeChecker2.h"
 #include "Luau/TypeFunction.h"
-#include "Luau/TypeInfer.h"
 #include "Luau/TypePack.h"
+#include "Luau/Type.h"
 #include "Luau/TypeUtils.h"
+#include "Luau/Subtyping.h"

 #include <algorithm>

@ -30,90 +29,81 @@
 */

 LUAU_FASTFLAG(LuauSolverV2)
-LUAU_FASTFLAG(LuauNonReentrantGeneralization2)
-LUAU_FASTFLAGVARIABLE(LuauTableCloneClonesType3)
-LUAU_FASTFLAGVARIABLE(LuauUserTypeFunTypecheck)
-LUAU_FASTFLAGVARIABLE(LuauMagicFreezeCheckBlocked)
-LUAU_FASTFLAGVARIABLE(LuauFormatUseLastPosition)
+LUAU_FASTFLAGVARIABLE(LuauTypestateBuiltins2)
+LUAU_FASTFLAGVARIABLE(LuauStringFormatArityFix)
+LUAU_FASTFLAGVARIABLE(LuauStringFormatErrorSuppression)
+LUAU_FASTFLAG(AutocompleteRequirePathSuggestions2)
+LUAU_FASTFLAG(LuauVectorDefinitionsExtra)
+LUAU_FASTFLAGVARIABLE(LuauTableCloneClonesType)
+LUAU_FASTFLAG(LuauTrackInteriorFreeTypesOnScope)

 namespace Luau
 {

 struct MagicSelect final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicSetMetatable final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicAssert final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicPack final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicRequire final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicClone final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicFreeze final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicFormat final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
    bool typeCheck(const MagicFunctionTypeCheckContext& ctx) override;
 };

 struct MagicMatch final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicGmatch final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

 struct MagicFind final : MagicFunction
 {
-    std::optional<WithPredicate<TypePackId>>
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
+    std::optional<WithPredicate<TypePackId>> handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>) override;
    bool infer(const MagicFunctionCallContext& ctx) override;
 };

@ -248,7 +238,6 @@ void addGlobalBinding(GlobalTypes& globals, const ScopePtr& scope, const std::st

 void addGlobalBinding(GlobalTypes& globals, const ScopePtr& scope, const std::string& name, Binding binding)
 {
-    inferGenericPolarities(NotNull{&globals.globalTypes}, NotNull{scope.get()}, binding.typeId);
    scope->bindings[globals.globalNames.names->getOrAdd(name.c_str())] = binding;
 }

@ -290,22 +279,6 @@ void assignPropDocumentationSymbols(TableType::Props& props, const std::string&
    }
 }

-static void finalizeGlobalBindings(ScopePtr scope)
-{
-    LUAU_ASSERT(FFlag::LuauUserTypeFunTypecheck);
-
-    for (const auto& pair : scope->bindings)
-    {
-        persist(pair.second.typeId);
-
-        if (TableType* ttv = getMutable<TableType>(pair.second.typeId))
-        {
-            if (!ttv->name)
-                ttv->name = "typeof(" + toString(pair.first) + ")";
-        }
-    }
-}
-
 void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeCheckForAutocomplete)
 {
    LUAU_ASSERT(!globals.globalTypes.types.isFrozen());
@ -313,9 +286,6 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC

    TypeArena& arena = globals.globalTypes;
    NotNull<BuiltinTypes> builtinTypes = globals.builtinTypes;
-    Scope* globalScope = nullptr; // NotNull<Scope> when removing FFlag::LuauNonReentrantGeneralization2
-    if (FFlag::LuauNonReentrantGeneralization2)
-        globalScope = globals.globalScope.get();

    if (FFlag::LuauSolverV2)
        builtinTypeFunctions().addToScope(NotNull{&arena}, NotNull{globals.globalScope.get()});
@ -325,8 +295,8 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC
    );
    LUAU_ASSERT(loadResult.success);

-    TypeId genericK = arena.addType(GenericType{globalScope, "K"});
-    TypeId genericV = arena.addType(GenericType{globalScope, "V"});
+    TypeId genericK = arena.addType(GenericType{"K"});
+    TypeId genericV = arena.addType(GenericType{"V"});
    TypeId mapOfKtoV = arena.addType(TableType{{}, TableIndexer(genericK, genericV), globals.globalScope->level, TableState::Generic});

    std::optional<TypeId> stringMetatableTy = getMetatable(builtinTypes->stringType, builtinTypes);
@ -340,25 +310,28 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC
    addGlobalBinding(globals, "string", it->second.type(), "@luau");

    // Setup 'vector' metatable
-    if (auto it = globals.globalScope->exportedTypeBindings.find("vector"); it != globals.globalScope->exportedTypeBindings.end())
+    if (FFlag::LuauVectorDefinitionsExtra)
    {
-        TypeId vectorTy = it->second.type;
-        ExternType* vectorCls = getMutable<ExternType>(vectorTy);
+        if (auto it = globals.globalScope->exportedTypeBindings.find("vector"); it != globals.globalScope->exportedTypeBindings.end())
+        {
+            TypeId vectorTy = it->second.type;
+            ClassType* vectorCls = getMutable<ClassType>(vectorTy);

-        vectorCls->metatable = arena.addType(TableType{{}, std::nullopt, TypeLevel{}, TableState::Sealed});
-        TableType* metatableTy = Luau::getMutable<TableType>(vectorCls->metatable);
+            vectorCls->metatable = arena.addType(TableType{{}, std::nullopt, TypeLevel{}, TableState::Sealed});
+            TableType* metatableTy = Luau::getMutable<TableType>(vectorCls->metatable);

-        metatableTy->props["__add"] = {makeFunction(arena, vectorTy, {vectorTy}, {vectorTy})};
-        metatableTy->props["__sub"] = {makeFunction(arena, vectorTy, {vectorTy}, {vectorTy})};
-        metatableTy->props["__unm"] = {makeFunction(arena, vectorTy, {}, {vectorTy})};
+            metatableTy->props["__add"] = {makeFunction(arena, vectorTy, {vectorTy}, {vectorTy})};
+            metatableTy->props["__sub"] = {makeFunction(arena, vectorTy, {vectorTy}, {vectorTy})};
+            metatableTy->props["__unm"] = {makeFunction(arena, vectorTy, {}, {vectorTy})};

-        std::initializer_list<TypeId> mulOverloads{
-            makeFunction(arena, vectorTy, {vectorTy}, {vectorTy}),
-            makeFunction(arena, vectorTy, {builtinTypes->numberType}, {vectorTy}),
-        };
-        metatableTy->props["__mul"] = {makeIntersection(arena, mulOverloads)};
-        metatableTy->props["__div"] = {makeIntersection(arena, mulOverloads)};
-        metatableTy->props["__idiv"] = {makeIntersection(arena, mulOverloads)};
+            std::initializer_list<TypeId> mulOverloads{
+                makeFunction(arena, vectorTy, {vectorTy}, {vectorTy}),
+                makeFunction(arena, vectorTy, {builtinTypes->numberType}, {vectorTy}),
+            };
+            metatableTy->props["__mul"] = {makeIntersection(arena, mulOverloads)};
+            metatableTy->props["__div"] = {makeIntersection(arena, mulOverloads)};
+            metatableTy->props["__idiv"] = {makeIntersection(arena, mulOverloads)};
+        }
    }

    // next<K, V>(t: Table<K, V>, i: K?) -> (K?, V)
@ -374,7 +347,7 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC
    // pairs<K, V>(t: Table<K, V>) -> ((Table<K, V>, K?) -> (K, V), Table<K, V>, nil)
    addGlobalBinding(globals, "pairs", arena.addType(FunctionType{{genericK, genericV}, {}, pairsArgsTypePack, pairsReturnTypePack}), "@luau");

-    TypeId genericMT = arena.addType(GenericType{globalScope, "MT"});
+    TypeId genericMT = arena.addType(GenericType{"MT"});

    TableType tab{TableState::Generic, globals.globalScope->level};
    TypeId tabTy = arena.addType(tab);
@ -386,7 +359,7 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC

    if (FFlag::LuauSolverV2)
    {
-        TypeId genericT = arena.addType(GenericType{globalScope, "T"});
+        TypeId genericT = arena.addType(GenericType{"T"});
        TypeId tMetaMT = arena.addType(MetatableType{genericT, genericMT});

        // clang-format off
@ -420,21 +393,14 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC
        // clang-format on
    }

-    if (FFlag::LuauUserTypeFunTypecheck)
+    for (const auto& pair : globals.globalScope->bindings)
    {
-        finalizeGlobalBindings(globals.globalScope);
-    }
-    else
-    {
-        for (const auto& pair : globals.globalScope->bindings)
-        {
-            persist(pair.second.typeId);
+        persist(pair.second.typeId);

-            if (TableType* ttv = getMutable<TableType>(pair.second.typeId))
-            {
-                if (!ttv->name)
-                    ttv->name = "typeof(" + toString(pair.first) + ")";
-            }
+        if (TableType* ttv = getMutable<TableType>(pair.second.typeId))
+        {
+            if (!ttv->name)
+                ttv->name = "typeof(" + toString(pair.first) + ")";
        }
    }

@ -443,7 +409,7 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC
    if (FFlag::LuauSolverV2)
    {
        // declare function assert<T>(value: T, errorMessage: string?): intersect<T, ~(false?)>
-        TypeId genericT = arena.addType(GenericType{globalScope, "T"});
+        TypeId genericT = arena.addType(GenericType{"T"});
        TypeId refinedTy = arena.addType(TypeFunctionInstanceType{
            NotNull{&builtinTypeFunctions().intersectFunc}, {genericT, arena.addType(NegationType{builtinTypes->falsyType})}, {}
        });
@ -466,16 +432,12 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC
            // the top table type.  We do the best we can by modelling these
            // functions using unconstrained generics.  It's not quite right,
            // but it'll be ok for now.
-            TypeId genericTy = arena.addType(GenericType{globalScope, "T"});
+            TypeId genericTy = arena.addType(GenericType{"T"});
            TypePackId thePack = arena.addTypePack({genericTy});
            TypeId idTyWithMagic = arena.addType(FunctionType{{genericTy}, {}, thePack, thePack});
            ttv->props["freeze"] = makeProperty(idTyWithMagic, "@luau/global/table.freeze");
-            if (globalScope)
-                inferGenericPolarities(NotNull{&globals.globalTypes}, NotNull{globalScope}, idTyWithMagic);

            TypeId idTy = arena.addType(FunctionType{{genericTy}, {}, thePack, thePack});
-            if (globalScope)
-                inferGenericPolarities(NotNull{&globals.globalTypes}, NotNull{globalScope}, idTy);
            ttv->props["clone"] = makeProperty(idTy, "@luau/global/table.clone");
        }
        else
@ -491,66 +453,21 @@ void registerBuiltinGlobals(Frontend& frontend, GlobalTypes& globals, bool typeC
        ttv->props["foreachi"].deprecated = true;

        attachMagicFunction(ttv->props["pack"].type(), std::make_shared<MagicPack>());
-        if (FFlag::LuauTableCloneClonesType3)
+        if (FFlag::LuauTableCloneClonesType)
            attachMagicFunction(ttv->props["clone"].type(), std::make_shared<MagicClone>());
-        attachMagicFunction(ttv->props["freeze"].type(), std::make_shared<MagicFreeze>());
+        if (FFlag::LuauTypestateBuiltins2)
+            attachMagicFunction(ttv->props["freeze"].type(), std::make_shared<MagicFreeze>());
    }

-    TypeId requireTy = getGlobalBinding(globals, "require");
-    attachTag(requireTy, kRequireTagName);
-    attachMagicFunction(requireTy, std::make_shared<MagicRequire>());
-
-    if (FFlag::LuauUserTypeFunTypecheck)
+    if (FFlag::AutocompleteRequirePathSuggestions2)
    {
-        // Global scope cannot be the parent of the type checking environment because it can be changed by the embedder
-        globals.globalTypeFunctionScope->exportedTypeBindings = globals.globalScope->exportedTypeBindings;
-        globals.globalTypeFunctionScope->builtinTypeNames = globals.globalScope->builtinTypeNames;
-
-        // Type function runtime also removes a few standard libraries and globals, so we will take only the ones that are defined
-        static const char* typeFunctionRuntimeBindings[] = {
-            // Libraries
-            "math",
-            "table",
-            "string",
-            "bit32",
-            "utf8",
-            "buffer",
-
-            // Globals
-            "assert",
-            "error",
-            "print",
-            "next",
-            "ipairs",
-            "pairs",
-            "select",
-            "unpack",
-            "getmetatable",
-            "setmetatable",
-            "rawget",
-            "rawset",
-            "rawlen",
-            "rawequal",
-            "tonumber",
-            "tostring",
-            "type",
-            "typeof",
-        };
-
-        for (auto& name : typeFunctionRuntimeBindings)
-        {
-            AstName astName = globals.globalNames.names->get(name);
-            LUAU_ASSERT(astName.value);
-
-            globals.globalTypeFunctionScope->bindings[astName] = globals.globalScope->bindings[astName];
-        }
-
-        LoadDefinitionFileResult typeFunctionLoadResult = frontend.loadDefinitionFile(
-            globals, globals.globalTypeFunctionScope, getTypeFunctionDefinitionSource(), "@luau", /* captureComments */ false, false
-        );
-        LUAU_ASSERT(typeFunctionLoadResult.success);
-
-        finalizeGlobalBindings(globals.globalTypeFunctionScope);
+        TypeId requireTy = getGlobalBinding(globals, "require");
+        attachTag(requireTy, kRequireTagName);
+        attachMagicFunction(requireTy, std::make_shared<MagicRequire>());
+    }
+    else
+    {
+        attachMagicFunction(getGlobalBinding(globals, "require"), std::make_shared<MagicRequire>());
    }
 }

@ -700,18 +617,13 @@ bool MagicFormat::typeCheck(const MagicFunctionTypeCheckContext& context)

    if (!fmt)
    {
-        context.typechecker->reportError(CountMismatch{1, std::nullopt, 0, CountMismatch::Arg, true, "string.format"}, context.callSite->location);
+        if (FFlag::LuauStringFormatArityFix)
+            context.typechecker->reportError(
+                CountMismatch{1, std::nullopt, 0, CountMismatch::Arg, true, "string.format"}, context.callSite->location
+            );
        return true;
    }

-    // CLI-150726: The block below effectively constructs a type pack and then type checks it by going parameter-by-parameter.
-    // This does _not_ handle cases like:
-    //
-    //  local foo : () -> (...string) = (nil :: any)
-    //  print(string.format("%s %d %s", foo()))
-    //
-    // ... which should be disallowed.
-
    std::vector<TypeId> expected = parseFormatString(context.builtinTypes, fmt->value.data, fmt->value.size);
    const auto& [params, tail] = flatten(context.arguments);

@ -723,25 +635,31 @@ bool MagicFormat::typeCheck(const MagicFunctionTypeCheckContext& context)
    {
        TypeId actualTy = params[i + paramOffset];
        TypeId expectedTy = expected[i];
-        Location location = FFlag::LuauFormatUseLastPosition
-            ? context.callSite->args.data[std::min(context.callSite->args.size - 1, i + (calledWithSelf ? 0 : paramOffset))]->location
-            : context.callSite->args.data[i + (calledWithSelf ? 0 : paramOffset)]->location;
+        Location location = context.callSite->args.data[i + (calledWithSelf ? 0 : paramOffset)]->location;
        // use subtyping instead here
        SubtypingResult result = context.typechecker->subtyping->isSubtype(actualTy, expectedTy, context.checkScope);

        if (!result.isSubtype)
        {
-            switch (shouldSuppressErrors(NotNull{&context.typechecker->normalizer}, actualTy))
+            if (FFlag::LuauStringFormatErrorSuppression)
            {
-            case ErrorSuppression::Suppress:
-                break;
-            case ErrorSuppression::NormalizationFailed:
-                break;
-            case ErrorSuppression::DoNotSuppress:
-                Reasonings reasonings = context.typechecker->explainReasonings(actualTy, expectedTy, location, result);
+                switch (shouldSuppressErrors(NotNull{&context.typechecker->normalizer}, actualTy))
+                {
+                    case ErrorSuppression::Suppress:
+                        break;
+                    case ErrorSuppression::NormalizationFailed:
+                        break;
+                    case ErrorSuppression::DoNotSuppress:
+                        Reasonings reasonings = context.typechecker->explainReasonings(actualTy, expectedTy, location, result);

-                if (!reasonings.suppressed)
-                    context.typechecker->reportError(TypeMismatch{expectedTy, actualTy, reasonings.toString()}, location);
+                        if (!reasonings.suppressed)
+                            context.typechecker->reportError(TypeMismatch{expectedTy, actualTy, reasonings.toString()}, location);
+                }
+            }
+            else
+            {
+                Reasonings reasonings = context.typechecker->explainReasonings(actualTy, expectedTy, location, result);
+                context.typechecker->reportError(TypeMismatch{expectedTy, actualTy, reasonings.toString()}, location);
            }
        }
    }
@ -1487,7 +1405,7 @@ std::optional<WithPredicate<TypePackId>> MagicClone::handleOldSolver(
    WithPredicate<TypePackId> withPredicate
 )
 {
-    LUAU_ASSERT(FFlag::LuauTableCloneClonesType3);
+    LUAU_ASSERT(FFlag::LuauTableCloneClonesType);

    auto [paramPack, _predicates] = withPredicate;

@ -1502,9 +1420,6 @@ std::optional<WithPredicate<TypePackId>> MagicClone::handleOldSolver(

    TypeId inputType = follow(paramTypes[0]);

-    if (!get<TableType>(inputType))
-        return std::nullopt;
-
    CloneState cloneState{typechecker.builtinTypes};
    TypeId resultType = shallowClone(inputType, arena, cloneState);

@ -1514,7 +1429,7 @@ std::optional<WithPredicate<TypePackId>> MagicClone::handleOldSolver(

 bool MagicClone::infer(const MagicFunctionCallContext& context)
 {
-    LUAU_ASSERT(FFlag::LuauTableCloneClonesType3);
+    LUAU_ASSERT(FFlag::LuauTableCloneClonesType);

    TypeArena* arena = context.solver->arena;

@ -1527,18 +1442,16 @@ bool MagicClone::infer(const MagicFunctionCallContext& context)

    TypeId inputType = follow(paramTypes[0]);

-    if (!get<TableType>(inputType))
-        return false;
-
    CloneState cloneState{context.solver->builtinTypes};
-    TypeId resultType = shallowClone(inputType, *arena, cloneState, /* ignorePersistent */ true);
+    TypeId resultType = shallowClone(inputType, *arena, cloneState);

    if (auto tableType = getMutable<TableType>(resultType))
    {
        tableType->scope = context.constraint->scope.get();
    }

-    trackInteriorFreeType(context.constraint->scope.get(), resultType);
+    if (FFlag::LuauTrackInteriorFreeTypesOnScope)
+        trackInteriorFreeType(context.constraint->scope.get(), resultType);

    TypePackId clonedTypePack = arena->addTypePack({resultType});
    asMutable(context.result)->ty.emplace<BoundTypePack>(clonedTypePack);
@ -1549,7 +1462,7 @@ bool MagicClone::infer(const MagicFunctionCallContext& context)
 static std::optional<TypeId> freezeTable(TypeId inputType, const MagicFunctionCallContext& context)
 {
    TypeArena* arena = context.solver->arena;
-    inputType = follow(inputType);
+
    if (auto mt = get<MetatableType>(inputType))
    {
        std::optional<TypeId> frozenTable = freezeTable(mt->table, context);
@ -1566,7 +1479,7 @@ static std::optional<TypeId> freezeTable(TypeId inputType, const MagicFunctionCa
    {
        // Clone the input type, this will become our final result type after we mutate it.
        CloneState cloneState{context.solver->builtinTypes};
-        TypeId resultType = shallowClone(inputType, *arena, cloneState, /* ignorePersistent */ true);
+        TypeId resultType = shallowClone(inputType, *arena, cloneState);
        auto tableTy = getMutable<TableType>(resultType);
        // `clone` should not break this.
        LUAU_ASSERT(tableTy);
@ -1591,14 +1504,15 @@ static std::optional<TypeId> freezeTable(TypeId inputType, const MagicFunctionCa
    return std::nullopt;
 }

-std::optional<WithPredicate<TypePackId>> MagicFreeze::
-    handleOldSolver(struct TypeChecker&, const std::shared_ptr<struct Scope>&, const class AstExprCall&, WithPredicate<TypePackId>)
+std::optional<WithPredicate<TypePackId>> MagicFreeze::handleOldSolver(struct TypeChecker &, const std::shared_ptr<struct Scope> &, const class AstExprCall &, WithPredicate<TypePackId>)
 {
    return std::nullopt;
 }

 bool MagicFreeze::infer(const MagicFunctionCallContext& context)
 {
+    LUAU_ASSERT(FFlag::LuauTypestateBuiltins2);
+
    TypeArena* arena = context.solver->arena;
    const DataFlowGraph* dfg = context.solver->dfg.get();
    Scope* scope = context.constraint->scope.get();
@ -1616,17 +1530,6 @@ bool MagicFreeze::infer(const MagicFunctionCallContext& context)
    std::optional<DefId> resultDef = dfg->getDefOptional(targetExpr);
    std::optional<TypeId> resultTy = resultDef ? scope->lookup(*resultDef) : std::nullopt;

-    if (FFlag::LuauMagicFreezeCheckBlocked)
-    {
-        if (resultTy && !get<BlockedType>(resultTy))
-        {
-            // If there's an existing result type but it's _not_ blocked, then
-            // we aren't type stating this builtin and should fall back to
-            // regular inference.
-            return false;
-        }
-    }
-
    std::optional<TypeId> frozenType = freezeTable(inputType, context);

    if (!frozenType)
--- a/Analysis/src/Clone.cpp
+++ b/Analysis/src/Clone.cpp
@ -1,20 +1,16 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
 #include "Luau/Clone.h"

-#include "Luau/Common.h"
 #include "Luau/NotNull.h"
 #include "Luau/Type.h"
 #include "Luau/TypePack.h"
 #include "Luau/Unifiable.h"
-#include "Luau/VisitType.h"

 LUAU_FASTFLAG(LuauSolverV2)

 // For each `Luau::clone` call, we will clone only up to N amount of types _and_ packs, as controlled by this limit.
 LUAU_FASTINTVARIABLE(LuauTypeCloneIterationLimit, 100'000)
-LUAU_FASTFLAGVARIABLE(LuauClonedTableAndFunctionTypesMustHaveScopes)
-LUAU_FASTFLAGVARIABLE(LuauDoNotClonePersistentBindings)
-LUAU_FASTFLAG(LuauIncrementalAutocompleteDemandBasedCloning)
+
 namespace Luau
 {

@ -31,8 +27,6 @@ const T* get(const Kind& kind)

 class TypeCloner
 {
-
-protected:
    NotNull<TypeArena> arena;
    NotNull<BuiltinTypes> builtinTypes;

@ -44,31 +38,17 @@ protected:
    NotNull<SeenTypes> types;
    NotNull<SeenTypePacks> packs;

-    TypeId forceTy = nullptr;
-    TypePackId forceTp = nullptr;
-
    int steps = 0;

 public:
-    TypeCloner(
-        NotNull<TypeArena> arena,
-        NotNull<BuiltinTypes> builtinTypes,
-        NotNull<SeenTypes> types,
-        NotNull<SeenTypePacks> packs,
-        TypeId forceTy,
-        TypePackId forceTp
-    )
+    TypeCloner(NotNull<TypeArena> arena, NotNull<BuiltinTypes> builtinTypes, NotNull<SeenTypes> types, NotNull<SeenTypePacks> packs)
        : arena(arena)
        , builtinTypes(builtinTypes)
        , types(types)
        , packs(packs)
-        , forceTy(forceTy)
-        , forceTp(forceTp)
    {
    }

-    virtual ~TypeCloner() = default;
-
    TypeId clone(TypeId ty)
    {
        shallowClone(ty);
@ -127,13 +107,12 @@ private:
        }
    }

-protected:
    std::optional<TypeId> find(TypeId ty) const
    {
        ty = follow(ty, FollowOption::DisableLazyTypeThunks);
        if (auto it = types->find(ty); it != types->end())
            return it->second;
-        else if (ty->persistent && ty != forceTy)
+        else if (ty->persistent)
            return ty;
        return std::nullopt;
    }
@ -143,7 +122,7 @@ protected:
        tp = follow(tp);
        if (auto it = packs->find(tp); it != packs->end())
            return it->second;
-        else if (tp->persistent && tp != forceTp)
+        else if (tp->persistent)
            return tp;
        return std::nullopt;
    }
@ -162,14 +141,14 @@ protected:
    }

 public:
-    virtual TypeId shallowClone(TypeId ty)
+    TypeId shallowClone(TypeId ty)
    {
        // We want to [`Luau::follow`] but without forcing the expansion of [`LazyType`]s.
        ty = follow(ty, FollowOption::DisableLazyTypeThunks);

        if (auto clone = find(ty))
            return *clone;
-        else if (ty->persistent && ty != forceTy)
+        else if (ty->persistent)
            return ty;

        TypeId target = arena->addType(ty->ty);
@ -179,6 +158,8 @@ public:
            generic->scope = nullptr;
        else if (auto free = getMutable<FreeType>(target))
            free->scope = nullptr;
+        else if (auto fn = getMutable<FunctionType>(target))
+            fn->scope = nullptr;
        else if (auto table = getMutable<TableType>(target))
            table->scope = nullptr;

@ -187,13 +168,13 @@ public:
        return target;
    }

-    virtual TypePackId shallowClone(TypePackId tp)
+    TypePackId shallowClone(TypePackId tp)
    {
        tp = follow(tp);

        if (auto clone = find(tp))
            return *clone;
-        else if (tp->persistent && tp != forceTp)
+        else if (tp->persistent)
            return tp;

        TypePackId target = arena->addTypePack(tp->ty);
@ -355,7 +336,7 @@ private:
        t->metatable = shallowClone(t->metatable);
    }

-    void cloneChildren(ExternType* t)
+    void cloneChildren(ClassType* t)
    {
        for (auto& [_, p] : t->props)
            p = shallowClone(p);
@ -395,7 +376,7 @@ private:
            ty = shallowClone(ty);
    }

-    virtual void cloneChildren(LazyType* t)
+    void cloneChildren(LazyType* t)
    {
        if (auto unwrapped = t->unwrapped.load())
            t->unwrapped.store(shallowClone(unwrapped));
@ -475,122 +456,23 @@ private:
    }
 };

-class FragmentAutocompleteTypeCloner final : public TypeCloner
-{
-    Scope* replacementForNullScope = nullptr;
-
-public:
-    FragmentAutocompleteTypeCloner(
-        NotNull<TypeArena> arena,
-        NotNull<BuiltinTypes> builtinTypes,
-        NotNull<SeenTypes> types,
-        NotNull<SeenTypePacks> packs,
-        TypeId forceTy,
-        TypePackId forceTp,
-        Scope* replacementForNullScope
-    )
-        : TypeCloner(arena, builtinTypes, types, packs, forceTy, forceTp)
-        , replacementForNullScope(replacementForNullScope)
-    {
-        LUAU_ASSERT(replacementForNullScope);
-    }
-
-    TypeId shallowClone(TypeId ty) override
-    {
-        // We want to [`Luau::follow`] but without forcing the expansion of [`LazyType`]s.
-        ty = follow(ty, FollowOption::DisableLazyTypeThunks);
-
-        if (auto clone = find(ty))
-            return *clone;
-        else if (ty->persistent && ty != forceTy)
-            return ty;
-
-        TypeId target = arena->addType(ty->ty);
-        asMutable(target)->documentationSymbol = ty->documentationSymbol;
-
-        if (auto generic = getMutable<GenericType>(target))
-            generic->scope = nullptr;
-        else if (auto free = getMutable<FreeType>(target))
-        {
-            free->scope = replacementForNullScope;
-        }
-        else if (auto tt = getMutable<TableType>(target))
-        {
-            if (FFlag::LuauClonedTableAndFunctionTypesMustHaveScopes)
-                tt->scope = replacementForNullScope;
-        }
-
-        (*types)[ty] = target;
-        queue.emplace_back(target);
-        return target;
-    }
-
-    TypePackId shallowClone(TypePackId tp) override
-    {
-        tp = follow(tp);
-
-        if (auto clone = find(tp))
-            return *clone;
-        else if (tp->persistent && tp != forceTp)
-            return tp;
-
-        TypePackId target = arena->addTypePack(tp->ty);
-
-        if (auto generic = getMutable<GenericTypePack>(target))
-            generic->scope = nullptr;
-        else if (auto free = getMutable<FreeTypePack>(target))
-            free->scope = replacementForNullScope;
-
-        (*packs)[tp] = target;
-        queue.emplace_back(target);
-        return target;
-    }
-
-    void cloneChildren(LazyType* t) override
-    {
-        // Do not clone lazy types
-        if (!FFlag::LuauIncrementalAutocompleteDemandBasedCloning)
-        {
-            if (auto unwrapped = t->unwrapped.load())
-                t->unwrapped.store(shallowClone(unwrapped));
-        }
-    }
-};
-
-
 } // namespace

-TypePackId shallowClone(TypePackId tp, TypeArena& dest, CloneState& cloneState, bool ignorePersistent)
+TypePackId shallowClone(TypePackId tp, TypeArena& dest, CloneState& cloneState)
 {
-    if (tp->persistent && !ignorePersistent)
+    if (tp->persistent)
        return tp;

-    TypeCloner cloner{
-        NotNull{&dest},
-        cloneState.builtinTypes,
-        NotNull{&cloneState.seenTypes},
-        NotNull{&cloneState.seenTypePacks},
-        nullptr,
-        ignorePersistent ? tp : nullptr
-    };
-
+    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}};
    return cloner.shallowClone(tp);
 }

-TypeId shallowClone(TypeId typeId, TypeArena& dest, CloneState& cloneState, bool ignorePersistent)
+TypeId shallowClone(TypeId typeId, TypeArena& dest, CloneState& cloneState)
 {
-    if (typeId->persistent && !ignorePersistent)
+    if (typeId->persistent)
        return typeId;

-    TypeCloner cloner{
-        NotNull{&dest},
-        cloneState.builtinTypes,
-        NotNull{&cloneState.seenTypes},
-        NotNull{&cloneState.seenTypePacks},
-        ignorePersistent ? typeId : nullptr,
-        nullptr
-    };
-
+    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}};
    return cloner.shallowClone(typeId);
 }

@ -599,7 +481,7 @@ TypePackId clone(TypePackId tp, TypeArena& dest, CloneState& cloneState)
    if (tp->persistent)
        return tp;

-    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}, nullptr, nullptr};
+    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}};
    return cloner.clone(tp);
 }

@ -608,13 +490,13 @@ TypeId clone(TypeId typeId, TypeArena& dest, CloneState& cloneState)
    if (typeId->persistent)
        return typeId;

-    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}, nullptr, nullptr};
+    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}};
    return cloner.clone(typeId);
 }

 TypeFun clone(const TypeFun& typeFun, TypeArena& dest, CloneState& cloneState)
 {
-    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}, nullptr, nullptr};
+    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}};

    TypeFun copy = typeFun;

@ -639,110 +521,4 @@ TypeFun clone(const TypeFun& typeFun, TypeArena& dest, CloneState& cloneState)
    return copy;
 }

-Binding clone(const Binding& binding, TypeArena& dest, CloneState& cloneState)
-{
-    TypeCloner cloner{NotNull{&dest}, cloneState.builtinTypes, NotNull{&cloneState.seenTypes}, NotNull{&cloneState.seenTypePacks}, nullptr, nullptr};
-
-    Binding b;
-    b.deprecated = binding.deprecated;
-    b.deprecatedSuggestion = binding.deprecatedSuggestion;
-    b.documentationSymbol = binding.documentationSymbol;
-    b.location = binding.location;
-    b.typeId = cloner.clone(binding.typeId);
-
-    return b;
-}
-
-TypePackId cloneIncremental(TypePackId tp, TypeArena& dest, CloneState& cloneState, Scope* freshScopeForFreeTypes)
-{
-    if (tp->persistent)
-        return tp;
-
-    FragmentAutocompleteTypeCloner cloner{
-        NotNull{&dest},
-        cloneState.builtinTypes,
-        NotNull{&cloneState.seenTypes},
-        NotNull{&cloneState.seenTypePacks},
-        nullptr,
-        nullptr,
-        freshScopeForFreeTypes
-    };
-    return cloner.clone(tp);
-}
-
-TypeId cloneIncremental(TypeId typeId, TypeArena& dest, CloneState& cloneState, Scope* freshScopeForFreeTypes)
-{
-    if (typeId->persistent)
-        return typeId;
-
-    FragmentAutocompleteTypeCloner cloner{
-        NotNull{&dest},
-        cloneState.builtinTypes,
-        NotNull{&cloneState.seenTypes},
-        NotNull{&cloneState.seenTypePacks},
-        nullptr,
-        nullptr,
-        freshScopeForFreeTypes
-    };
-    return cloner.clone(typeId);
-}
-
-TypeFun cloneIncremental(const TypeFun& typeFun, TypeArena& dest, CloneState& cloneState, Scope* freshScopeForFreeTypes)
-{
-    FragmentAutocompleteTypeCloner cloner{
-        NotNull{&dest},
-        cloneState.builtinTypes,
-        NotNull{&cloneState.seenTypes},
-        NotNull{&cloneState.seenTypePacks},
-        nullptr,
-        nullptr,
-        freshScopeForFreeTypes
-    };
-
-    TypeFun copy = typeFun;
-
-    for (auto& param : copy.typeParams)
-    {
-        param.ty = cloner.clone(param.ty);
-
-        if (param.defaultValue)
-            param.defaultValue = cloner.clone(*param.defaultValue);
-    }
-
-    for (auto& param : copy.typePackParams)
-    {
-        param.tp = cloner.clone(param.tp);
-
-        if (param.defaultValue)
-            param.defaultValue = cloner.clone(*param.defaultValue);
-    }
-
-    copy.type = cloner.clone(copy.type);
-
-    return copy;
-}
-
-Binding cloneIncremental(const Binding& binding, TypeArena& dest, CloneState& cloneState, Scope* freshScopeForFreeTypes)
-{
-    FragmentAutocompleteTypeCloner cloner{
-        NotNull{&dest},
-        cloneState.builtinTypes,
-        NotNull{&cloneState.seenTypes},
-        NotNull{&cloneState.seenTypePacks},
-        nullptr,
-        nullptr,
-        freshScopeForFreeTypes
-    };
-
-    Binding b;
-    b.deprecated = binding.deprecated;
-    b.deprecatedSuggestion = binding.deprecatedSuggestion;
-    b.documentationSymbol = binding.documentationSymbol;
-    b.location = binding.location;
-    b.typeId = FFlag::LuauDoNotClonePersistentBindings && binding.typeId->persistent ? binding.typeId : cloner.clone(binding.typeId);
-
-    return b;
-}
-
-
 } // namespace Luau
--- a/Analysis/src/Constraint.cpp
+++ b/Analysis/src/Constraint.cpp
@ -3,8 +3,6 @@
 #include "Luau/Constraint.h"
 #include "Luau/VisitType.h"

-LUAU_FASTFLAG(DebugLuauGreedyGeneralization)
-
 namespace Luau
 {

@ -20,7 +18,7 @@ struct ReferenceCountInitializer : TypeOnceVisitor

    DenseHashSet<TypeId>* result;

-    explicit ReferenceCountInitializer(DenseHashSet<TypeId>* result)
+    ReferenceCountInitializer(DenseHashSet<TypeId>* result)
        : result(result)
    {
    }
@ -43,15 +41,24 @@ struct ReferenceCountInitializer : TypeOnceVisitor
        return false;
    }

-    bool visit(TypeId ty, const ExternType&) override
+    bool visit(TypeId ty, const ClassType&) override
    {
-        // ExternTypes never contain free types.
+        // ClassTypes never contain free types.
        return false;
    }

    bool visit(TypeId, const TypeFunctionInstanceType&) override
    {
-        return FFlag::DebugLuauGreedyGeneralization;
+        // We do not consider reference counted types that are inside a type
+        // function to be part of the reachable reference counted types.
+        // Otherwise, code can be constructed in just the right way such
+        // that two type functions both claim to mutate a free type, which
+        // prevents either type function from trying to generalize it, so
+        // we potentially get stuck.
+        //
+        // The default behavior here is `true` for "visit the child types"
+        // of this type, hence:
+        return false;
    }
 };

@ -104,11 +111,6 @@ DenseHashSet<TypeId> Constraint::getMaybeMutatedFreeTypes() const
    {
        rci.traverse(fchc->argsPack);
    }
-    else if (auto fcc = get<FunctionCallConstraint>(*this); fcc && FFlag::DebugLuauGreedyGeneralization)
-    {
-        rci.traverse(fcc->fn);
-        rci.traverse(fcc->argsPack);
-    }
    else if (auto ptc = get<PrimitiveTypeConstraint>(*this))
    {
        rci.traverse(ptc->freeType);
@ -116,15 +118,12 @@ DenseHashSet<TypeId> Constraint::getMaybeMutatedFreeTypes() const
    else if (auto hpc = get<HasPropConstraint>(*this))
    {
        rci.traverse(hpc->resultType);
-        if (FFlag::DebugLuauGreedyGeneralization)
-            rci.traverse(hpc->subjectType);
+        // `HasPropConstraints` should not mutate `subjectType`.
    }
    else if (auto hic = get<HasIndexerConstraint>(*this))
    {
-        if (FFlag::DebugLuauGreedyGeneralization)
-            rci.traverse(hic->subjectType);
        rci.traverse(hic->resultType);
-        // `HasIndexerConstraint` should not mutate `indexType`.
+        // `HasIndexerConstraint` should not mutate `subjectType` or `indexType`.
    }
    else if (auto apc = get<AssignPropConstraint>(*this))
    {
@ -143,18 +142,10 @@ DenseHashSet<TypeId> Constraint::getMaybeMutatedFreeTypes() const
            rci.traverse(ty);
        // `UnpackConstraint` should not mutate `sourcePack`.
    }
-    else if (auto rpc = get<ReduceConstraint>(*this); FFlag::DebugLuauGreedyGeneralization && rpc)
-    {
-        rci.traverse(rpc->ty);
-    }
    else if (auto rpc = get<ReducePackConstraint>(*this))
    {
        rci.traverse(rpc->tp);
    }
-    else if (auto tcc = get<TableCheckConstraint>(*this))
-    {
-        rci.traverse(tcc->exprType);
-    }

    return types;
 }
--- a/Analysis/src/ConstraintGenerator.cpp
+++ b/Analysis/src/ConstraintGenerator.cpp
--- a/Analysis/src/ConstraintSolver.cpp
+++ b/Analysis/src/ConstraintSolver.cpp
--- a/Analysis/src/DataFlowGraph.cpp
+++ b/Analysis/src/DataFlowGraph.cpp
@ -13,25 +13,33 @@

 LUAU_FASTFLAG(DebugLuauFreezeArena)
 LUAU_FASTFLAG(LuauSolverV2)
-LUAU_FASTFLAGVARIABLE(LuauPreprocessTypestatedArgument)
-LUAU_FASTFLAGVARIABLE(LuauDfgScopeStackTrueReset)
-LUAU_FASTFLAGVARIABLE(LuauDfgScopeStackNotNull)
-LUAU_FASTFLAG(LuauStoreReturnTypesAsPackOnAst)
-LUAU_FASTFLAGVARIABLE(LuauDoNotAddUpvalueTypesToLocalType)
-LUAU_FASTFLAGVARIABLE(LuauDfgIfBlocksShouldRespectControlFlow)
+LUAU_FASTFLAG(LuauTypestateBuiltins2)
+
 namespace Luau
 {

 bool doesCallError(const AstExprCall* call); // TypeInfer.cpp

+struct ReferencedDefFinder : public AstVisitor
+{
+    bool visit(AstExprLocal* local) override
+    {
+        referencedLocalDefs.push_back(local->local);
+        return true;
+    }
+    // ast defs is just a mapping from expr -> def in general
+    // will get built up by the dfg builder
+
+    // localDefs, we need to copy over
+    std::vector<AstLocal*> referencedLocalDefs;
+};
+
 struct PushScope
 {
    ScopeStack& stack;
-    size_t previousSize;

    PushScope(ScopeStack& stack, DfgScope* scope)
        : stack(stack)
-        , previousSize(stack.size())
    {
        // `scope` should never be `nullptr` here.
        LUAU_ASSERT(scope);
@ -40,18 +48,7 @@ struct PushScope

    ~PushScope()
    {
-        if (FFlag::LuauDfgScopeStackTrueReset)
-        {
-            // If somehow this stack has _shrunk_ to be smaller than we expect,
-            // something very strange has happened.
-            LUAU_ASSERT(stack.size() > previousSize);
-            while (stack.size() > previousSize)
-                stack.pop_back();
-        }
-        else
-        {
-            stack.pop_back();
-        }
+        stack.pop_back();
    }
 };

@ -86,6 +83,12 @@ std::optional<DefId> DataFlowGraph::getDefOptional(const AstExpr* expr) const
    return NotNull{*def};
 }

+std::optional<DefId> DataFlowGraph::getRValueDefForCompoundAssign(const AstExpr* expr) const
+{
+    auto def = compoundAssignDefs.find(expr);
+    return def ? std::optional<DefId>(*def) : std::nullopt;
+}
+
 DefId DataFlowGraph::getDef(const AstLocal* local) const
 {
    auto def = localDefs.find(local);
@ -199,15 +202,7 @@ DataFlowGraph DataFlowGraphBuilder::build(

    DataFlowGraphBuilder builder(defArena, keyArena);
    builder.handle = handle;
-
-    DfgScope* moduleScope;
-    // We're not explicitly calling makeChildScope here because that function relies on currentScope
-    // which guarantees that the scope being returned is NotNull
-    // This means that while the scope stack is empty, we'll have to manually initialize the global scope
-    if (FFlag::LuauDfgScopeStackNotNull)
-        moduleScope = builder.scopes.emplace_back(new DfgScope{nullptr, DfgScope::ScopeType::Linear}).get();
-    else
-        moduleScope = builder.makeChildScope();
+    DfgScope* moduleScope = builder.makeChildScope();
    PushScope ps{builder.scopeStack, moduleScope};
    builder.visitBlockWithoutChildScope(block);
    builder.resolveCaptures();
@ -239,13 +234,7 @@ void DataFlowGraphBuilder::resolveCaptures()
    }
 }

-NotNull<DfgScope> DataFlowGraphBuilder::currentScope()
-{
-    LUAU_ASSERT(!scopeStack.empty());
-    return NotNull{scopeStack.back()};
-}
-
-DfgScope* DataFlowGraphBuilder::currentScope_DEPRECATED()
+DfgScope* DataFlowGraphBuilder::currentScope()
 {
    if (scopeStack.empty())
        return nullptr; // nullptr is the root DFG scope.
@ -254,10 +243,7 @@ DfgScope* DataFlowGraphBuilder::currentScope_DEPRECATED()

 DfgScope* DataFlowGraphBuilder::makeChildScope(DfgScope::ScopeType scopeType)
 {
-    if (FFlag::LuauDfgScopeStackNotNull)
-        return scopes.emplace_back(new DfgScope{currentScope(), scopeType}).get();
-    else
-        return scopes.emplace_back(new DfgScope{currentScope_DEPRECATED(), scopeType}).get();
+    return scopes.emplace_back(new DfgScope{currentScope(), scopeType}).get();
 }

 void DataFlowGraphBuilder::join(DfgScope* p, DfgScope* a, DfgScope* b)
@ -332,9 +318,9 @@ void DataFlowGraphBuilder::joinProps(DfgScope* result, const DfgScope& a, const
    }
 }

-DefId DataFlowGraphBuilder::lookup(Symbol symbol, Location location)
+DefId DataFlowGraphBuilder::lookup(Symbol symbol)
 {
-    DfgScope* scope = FFlag::LuauDfgScopeStackNotNull ? currentScope() : currentScope_DEPRECATED();
+    DfgScope* scope = currentScope();

    // true if any of the considered scopes are a loop.
    bool outsideLoopScope = false;
@ -359,15 +345,15 @@ DefId DataFlowGraphBuilder::lookup(Symbol symbol, Location location)
        }
    }

-    DefId result = defArena->freshCell(symbol, location);
+    DefId result = defArena->freshCell();
    scope->bindings[symbol] = result;
    captures[symbol].allVersions.push_back(result);
    return result;
 }

-DefId DataFlowGraphBuilder::lookup(DefId def, const std::string& key, Location location)
+DefId DataFlowGraphBuilder::lookup(DefId def, const std::string& key)
 {
-    DfgScope* scope = FFlag::LuauDfgScopeStackNotNull ? currentScope() : currentScope_DEPRECATED();
+    DfgScope* scope = currentScope();
    for (DfgScope* current = scope; current; current = current->parent)
    {
        if (auto props = current->props.find(def))
@ -377,7 +363,7 @@ DefId DataFlowGraphBuilder::lookup(DefId def, const std::string& key, Location l
        }
        else if (auto phi = get<Phi>(def); phi && phi->operands.empty()) // Unresolved phi nodes
        {
-            DefId result = defArena->freshCell(def->name, location);
+            DefId result = defArena->freshCell();
            scope->props[def][key] = result;
            return result;
        }
@ -387,7 +373,7 @@ DefId DataFlowGraphBuilder::lookup(DefId def, const std::string& key, Location l
    {
        std::vector<DefId> defs;
        for (DefId operand : phi->operands)
-            defs.push_back(lookup(operand, key, location));
+            defs.push_back(lookup(operand, key));

        DefId result = defArena->phi(defs);
        scope->props[def][key] = result;
@ -395,7 +381,7 @@ DefId DataFlowGraphBuilder::lookup(DefId def, const std::string& key, Location l
    }
    else if (get<Cell>(def))
    {
-        DefId result = defArena->freshCell(def->name, location);
+        DefId result = defArena->freshCell();
        scope->props[def][key] = result;
        return result;
    }
@ -413,10 +399,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatBlock* b)
        cf = visitBlockWithoutChildScope(b);
    }

-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->inherit(child);
-    else
-        currentScope_DEPRECATED()->inherit(child);
+    currentScope()->inherit(child);
    return cf;
 }

@ -473,7 +456,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStat* s)
        return visit(d);
    else if (auto d = s->as<AstStatDeclareFunction>())
        return visit(d);
-    else if (auto d = s->as<AstStatDeclareExternType>())
+    else if (auto d = s->as<AstStatDeclareClass>())
        return visit(d);
    else if (auto error = s->as<AstStatError>())
        return visit(error);
@ -501,27 +484,13 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatIf* i)
        elsecf = visit(i->elsebody);
    }

-    DfgScope* scope = FFlag::LuauDfgScopeStackNotNull ? currentScope() : currentScope_DEPRECATED();
-    if (FFlag::LuauDfgIfBlocksShouldRespectControlFlow)
-    {
-        // If the control flow from the `if` or `else` block is non-linear,
-        // then we should assume that the _other_ branch is the one taken.
-        if (thencf != ControlFlow::None && elsecf == ControlFlow::None)
-            scope->inherit(elseScope);
-        else if (thencf == ControlFlow::None && elsecf != ControlFlow::None)
-            scope->inherit(thenScope);
-        else if ((thencf | elsecf) == ControlFlow::None)
-            join(scope, thenScope, elseScope);
-    }
-    else
-    {
-        if (thencf != ControlFlow::None && elsecf == ControlFlow::None)
-            join(scope, scope, elseScope);
-        else if (thencf == ControlFlow::None && elsecf != ControlFlow::None)
-            join(scope, thenScope, scope);
-        else if ((thencf | elsecf) == ControlFlow::None)
-            join(scope, thenScope, elseScope);
-    }
+    DfgScope* scope = currentScope();
+    if (thencf != ControlFlow::None && elsecf == ControlFlow::None)
+        join(scope, scope, elseScope);
+    else if (thencf == ControlFlow::None && elsecf != ControlFlow::None)
+        join(scope, thenScope, scope);
+    else if ((thencf | elsecf) == ControlFlow::None)
+        join(scope, thenScope, elseScope);

    if (thencf == elsecf)
        return thencf;
@ -542,10 +511,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatWhile* w)
        visit(w->body);
    }

-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->inherit(whileScope);
-    else
-        currentScope_DEPRECATED()->inherit(whileScope);
+    currentScope()->inherit(whileScope);

    return ControlFlow::None;
 }
@ -561,10 +527,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatRepeat* r)
        visitExpr(r->condition);
    }

-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->inherit(repeatScope);
-    else
-        currentScope_DEPRECATED()->inherit(repeatScope);
+    currentScope()->inherit(repeatScope);

    return ControlFlow::None;
 }
@ -613,7 +576,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatLocal* l)
        // We need to create a new def to intentionally avoid alias tracking, but we'd like to
        // make sure that the non-aliased defs are also marked as a subscript for refinements.
        bool subscripted = i < defs.size() && containsSubscriptedDefinition(defs[i]);
-        DefId def = defArena->freshCell(local, local->location, subscripted);
+        DefId def = defArena->freshCell(subscripted);
        if (i < l->values.size)
        {
            AstExpr* e = l->values.data[i];
@ -623,10 +586,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatLocal* l)
            }
        }
        graph.localDefs[local] = def;
-        if (FFlag::LuauDfgScopeStackNotNull)
-            currentScope()->bindings[local] = def;
-        else
-            currentScope_DEPRECATED()->bindings[local] = def;
+        currentScope()->bindings[local] = def;
        captures[local].allVersions.push_back(def);
    }

@ -648,22 +608,16 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatFor* f)
        if (f->var->annotation)
            visitType(f->var->annotation);

-        DefId def = defArena->freshCell(f->var, f->var->location);
+        DefId def = defArena->freshCell();
        graph.localDefs[f->var] = def;
-        if (FFlag::LuauDfgScopeStackNotNull)
-            currentScope()->bindings[f->var] = def;
-        else
-            currentScope_DEPRECATED()->bindings[f->var] = def;
+        currentScope()->bindings[f->var] = def;
        captures[f->var].allVersions.push_back(def);

        // TODO(controlflow): entry point has a back edge from exit point
        visit(f->body);
    }

-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->inherit(forScope);
-    else
-        currentScope_DEPRECATED()->inherit(forScope);
+    currentScope()->inherit(forScope);

    return ControlFlow::None;
 }
@ -680,12 +634,9 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatForIn* f)
            if (local->annotation)
                visitType(local->annotation);

-            DefId def = defArena->freshCell(local, local->location);
+            DefId def = defArena->freshCell();
            graph.localDefs[local] = def;
-            if (FFlag::LuauDfgScopeStackNotNull)
-                currentScope()->bindings[local] = def;
-            else
-                currentScope_DEPRECATED()->bindings[local] = def;
+            currentScope()->bindings[local] = def;
            captures[local].allVersions.push_back(def);
        }

@ -696,10 +647,8 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatForIn* f)

        visit(f->body);
    }
-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->inherit(forScope);
-    else
-        currentScope_DEPRECATED()->inherit(forScope);
+
+    currentScope()->inherit(forScope);

    return ControlFlow::None;
 }
@ -714,7 +663,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatAssign* a)
    for (size_t i = 0; i < a->vars.size; ++i)
    {
        AstExpr* v = a->vars.data[i];
-        visitLValue(v, i < defs.size() ? defs[i] : defArena->freshCell(Symbol{}, v->location));
+        visitLValue(v, i < defs.size() ? defs[i] : defArena->freshCell());
    }

    return ControlFlow::None;
@ -740,7 +689,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatFunction* f)
    //
    // which is evidence that references to variables must be a phi node of all possible definitions,
    // but for bug compatibility, we'll assume the same thing here.
-    visitLValue(f->name, defArena->freshCell(Symbol{}, f->name->location));
+    visitLValue(f->name, defArena->freshCell());
    visitExpr(f->func);

    if (auto local = f->name->as<AstExprLocal>())
@ -760,12 +709,9 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatFunction* f)

 ControlFlow DataFlowGraphBuilder::visit(AstStatLocalFunction* l)
 {
-    DefId def = defArena->freshCell(l->name, l->location);
+    DefId def = defArena->freshCell();
    graph.localDefs[l->name] = def;
-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->bindings[l->name] = def;
-    else
-        currentScope_DEPRECATED()->bindings[l->name] = def;
+    currentScope()->bindings[l->name] = def;
    captures[l->name].allVersions.push_back(def);
    visitExpr(l->func);

@ -796,12 +742,9 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatTypeFunction* f)

 ControlFlow DataFlowGraphBuilder::visit(AstStatDeclareGlobal* d)
 {
-    DefId def = defArena->freshCell(d->name, d->nameLocation);
+    DefId def = defArena->freshCell();
    graph.declaredDefs[d] = def;
-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->bindings[d->name] = def;
-    else
-        currentScope_DEPRECATED()->bindings[d->name] = def;
+    currentScope()->bindings[d->name] = def;
    captures[d->name].allVersions.push_back(def);

    visitType(d->type);
@ -811,12 +754,9 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatDeclareGlobal* d)

 ControlFlow DataFlowGraphBuilder::visit(AstStatDeclareFunction* d)
 {
-    DefId def = defArena->freshCell(d->name, d->nameLocation);
+    DefId def = defArena->freshCell();
    graph.declaredDefs[d] = def;
-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->bindings[d->name] = def;
-    else
-        currentScope_DEPRECATED()->bindings[d->name] = def;
+    currentScope()->bindings[d->name] = def;
    captures[d->name].allVersions.push_back(def);

    DfgScope* unreachable = makeChildScope();
@ -825,15 +765,12 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatDeclareFunction* d)
    visitGenerics(d->generics);
    visitGenericPacks(d->genericPacks);
    visitTypeList(d->params);
-    if (FFlag::LuauStoreReturnTypesAsPackOnAst)
-        visitTypePack(d->retTypes);
-    else
-        visitTypeList(d->retTypes_DEPRECATED);
+    visitTypeList(d->retTypes);

    return ControlFlow::None;
 }

-ControlFlow DataFlowGraphBuilder::visit(AstStatDeclareExternType* d)
+ControlFlow DataFlowGraphBuilder::visit(AstStatDeclareClass* d)
 {
    // This declaration does not "introduce" any bindings in value namespace,
    // so there's no symbolic value to begin with. We'll traverse the properties
@ -841,7 +778,7 @@ ControlFlow DataFlowGraphBuilder::visit(AstStatDeclareExternType* d)
    DfgScope* unreachable = makeChildScope();
    PushScope ps{scopeStack, unreachable};

-    for (AstDeclaredExternTypeProperty prop : d->props)
+    for (AstDeclaredClassProp prop : d->props)
        visitType(prop.ty);

    return ControlFlow::None;
@ -874,19 +811,19 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExpr* e)
        if (auto g = e->as<AstExprGroup>())
            return visitExpr(g);
        else if (auto c = e->as<AstExprConstantNil>())
-            return {defArena->freshCell(Symbol{}, c->location), nullptr}; // ok
+            return {defArena->freshCell(), nullptr}; // ok
        else if (auto c = e->as<AstExprConstantBool>())
-            return {defArena->freshCell(Symbol{}, c->location), nullptr}; // ok
+            return {defArena->freshCell(), nullptr}; // ok
        else if (auto c = e->as<AstExprConstantNumber>())
-            return {defArena->freshCell(Symbol{}, c->location), nullptr}; // ok
+            return {defArena->freshCell(), nullptr}; // ok
        else if (auto c = e->as<AstExprConstantString>())
-            return {defArena->freshCell(Symbol{}, c->location), nullptr}; // ok
+            return {defArena->freshCell(), nullptr}; // ok
        else if (auto l = e->as<AstExprLocal>())
            return visitExpr(l);
        else if (auto g = e->as<AstExprGlobal>())
            return visitExpr(g);
        else if (auto v = e->as<AstExprVarargs>())
-            return {defArena->freshCell(Symbol{}, v->location), nullptr}; // ok
+            return {defArena->freshCell(), nullptr}; // ok
        else if (auto c = e->as<AstExprCall>())
            return visitExpr(c);
        else if (auto i = e->as<AstExprIndexName>())
@ -927,14 +864,14 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprGroup* group)

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprLocal* l)
 {
-    DefId def = lookup(l->local, l->local->location);
+    DefId def = lookup(l->local);
    const RefinementKey* key = keyArena->leaf(def);
    return {def, key};
 }

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprGlobal* g)
 {
-    DefId def = lookup(g->name, g->location);
+    DefId def = lookup(g->name);
    return {def, keyArena->leaf(def)};
 }

@ -942,13 +879,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprCall* c)
 {
    visitExpr(c->func);

-    if (FFlag::LuauPreprocessTypestatedArgument)
-    {
-        for (AstExpr* arg : c->args)
-            visitExpr(arg);
-    }
-
-    if (shouldTypestateForFirstArgument(*c) && c->args.size > 1 && isLValue(*c->args.begin()))
+    if (FFlag::LuauTypestateBuiltins2 && shouldTypestateForFirstArgument(*c) && c->args.size > 1 && isLValue(*c->args.begin()))
    {
        AstExpr* firstArg = *c->args.begin();

@ -978,23 +909,11 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprCall* c)
        visitLValue(firstArg, def);
    }

-    if (!FFlag::LuauPreprocessTypestatedArgument)
-    {
-        for (AstExpr* arg : c->args)
-            visitExpr(arg);
-    }
+    for (AstExpr* arg : c->args)
+        visitExpr(arg);

-    // We treat function calls as "subscripted" as they could potentially
-    // return a subscripted value, consider:
-    //
-    //  local function foo(tbl: {[string]: woof)
-    //      return tbl["foobarbaz"]
-    //  end
-    //
-    //  local v = foo({})
-    //
-    // We want to consider `v` to be subscripted here.
-    return {defArena->freshCell(Symbol{}, c->location, /*subscripted=*/true)};
+    // calls should be treated as subscripted.
+    return {defArena->freshCell(/* subscripted */ true), nullptr};
 }

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprIndexName* i)
@ -1002,7 +921,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprIndexName* i)
    auto [parentDef, parentKey] = visitExpr(i->expr);
    std::string index = i->index.value;

-    DefId def = lookup(parentDef, index, i->location);
+    DefId def = lookup(parentDef, index);
    return {def, keyArena->node(parentKey, def, index)};
 }

@ -1015,11 +934,11 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprIndexExpr* i)
    {
        std::string index{string->value.data, string->value.size};

-        DefId def = lookup(parentDef, index, i->location);
+        DefId def = lookup(parentDef, index);
        return {def, keyArena->node(parentKey, def, index)};
    }

-    return {defArena->freshCell(Symbol{}, i->location, /* subscripted= */ true), nullptr};
+    return {defArena->freshCell(/* subscripted= */ true), nullptr};
 }

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprFunction* f)
@ -1032,7 +951,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprFunction* f)
        // There's no syntax for `self` to have an annotation if using `function t:m()`
        LUAU_ASSERT(!self->annotation);

-        DefId def = defArena->freshCell(f->debugname, f->location);
+        DefId def = defArena->freshCell();
        graph.localDefs[self] = def;
        signatureScope->bindings[self] = def;
        captures[self].allVersions.push_back(def);
@ -1043,7 +962,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprFunction* f)
        if (param->annotation)
            visitType(param->annotation);

-        DefId def = defArena->freshCell(param, param->location);
+        DefId def = defArena->freshCell();
        graph.localDefs[param] = def;
        signatureScope->bindings[param] = def;
        captures[param].allVersions.push_back(def);
@ -1052,16 +971,8 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprFunction* f)
    if (f->varargAnnotation)
        visitTypePack(f->varargAnnotation);

-    if (FFlag::LuauStoreReturnTypesAsPackOnAst)
-    {
-        if (f->returnAnnotation)
-            visitTypePack(f->returnAnnotation);
-    }
-    else
-    {
-        if (f->returnAnnotation_DEPRECATED)
-            visitTypeList(*f->returnAnnotation_DEPRECATED);
-    }
+    if (f->returnAnnotation)
+        visitTypeList(*f->returnAnnotation);

    // TODO: function body can be re-entrant, as in mutations that occurs at the end of the function can also be
    // visible to the beginning of the function, so statically speaking, the body of the function has an exit point
@ -1073,16 +984,13 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprFunction* f)
    // g() --> 5
    visit(f->body);

-    return {defArena->freshCell(f->debugname, f->location), nullptr};
+    return {defArena->freshCell(), nullptr};
 }

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprTable* t)
 {
-    DefId tableCell = defArena->freshCell(Symbol{}, t->location);
-    if (FFlag::LuauDfgScopeStackNotNull)
-        currentScope()->props[tableCell] = {};
-    else
-        currentScope_DEPRECATED()->props[tableCell] = {};
+    DefId tableCell = defArena->freshCell();
+    currentScope()->props[tableCell] = {};
    for (AstExprTable::Item item : t->items)
    {
        DataFlowResult result = visitExpr(item.value);
@ -1090,12 +998,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprTable* t)
        {
            visitExpr(item.key);
            if (auto string = item.key->as<AstExprConstantString>())
-            {
-                if (FFlag::LuauDfgScopeStackNotNull)
-                    currentScope()->props[tableCell][string->value.data] = result.def;
-                else
-                    currentScope_DEPRECATED()->props[tableCell][string->value.data] = result.def;
-            }
+                currentScope()->props[tableCell][string->value.data] = result.def;
        }
    }

@ -1106,7 +1009,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprUnary* u)
 {
    visitExpr(u->expr);

-    return {defArena->freshCell(Symbol{}, u->location), nullptr};
+    return {defArena->freshCell(), nullptr};
 }

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprBinary* b)
@ -1114,7 +1017,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprBinary* b)
    visitExpr(b->left);
    visitExpr(b->right);

-    return {defArena->freshCell(Symbol{}, b->location), nullptr};
+    return {defArena->freshCell(), nullptr};
 }

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprTypeAssertion* t)
@ -1131,7 +1034,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprIfElse* i)
    visitExpr(i->trueExpr);
    visitExpr(i->falseExpr);

-    return {defArena->freshCell(Symbol{}, i->location), nullptr};
+    return {defArena->freshCell(), nullptr};
 }

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprInterpString* i)
@ -1139,7 +1042,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprInterpString* i)
    for (AstExpr* e : i->expressions)
        visitExpr(e);

-    return {defArena->freshCell(Symbol{}, i->location), nullptr};
+    return {defArena->freshCell(), nullptr};
 }

 DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprError* error)
@ -1150,7 +1053,7 @@ DataFlowResult DataFlowGraphBuilder::visitExpr(AstExprError* error)
    for (AstExpr* e : error->expressions)
        visitExpr(e);

-    return {defArena->freshCell(Symbol{}, error->location), nullptr};
+    return {defArena->freshCell(), nullptr};
 }

 void DataFlowGraphBuilder::visitLValue(AstExpr* e, DefId incomingDef)
@ -1176,12 +1079,12 @@ void DataFlowGraphBuilder::visitLValue(AstExpr* e, DefId incomingDef)

 DefId DataFlowGraphBuilder::visitLValue(AstExprLocal* l, DefId incomingDef)
 {
-    DfgScope* scope = FFlag::LuauDfgScopeStackNotNull ? currentScope() : currentScope_DEPRECATED();
+    DfgScope* scope = currentScope();

    // In order to avoid alias tracking, we need to clip the reference to the parent def.
-    if (scope->canUpdateDefinition(l->local) && !(FFlag::LuauDoNotAddUpvalueTypesToLocalType && l->upvalue))
+    if (scope->canUpdateDefinition(l->local))
    {
-        DefId updated = defArena->freshCell(l->local, l->location, containsSubscriptedDefinition(incomingDef));
+        DefId updated = defArena->freshCell(containsSubscriptedDefinition(incomingDef));
        scope->bindings[l->local] = updated;
        captures[l->local].allVersions.push_back(updated);
        return updated;
@ -1192,12 +1095,12 @@ DefId DataFlowGraphBuilder::visitLValue(AstExprLocal* l, DefId incomingDef)

 DefId DataFlowGraphBuilder::visitLValue(AstExprGlobal* g, DefId incomingDef)
 {
-    DfgScope* scope = FFlag::LuauDfgScopeStackNotNull ? currentScope() : currentScope_DEPRECATED();
+    DfgScope* scope = currentScope();

    // In order to avoid alias tracking, we need to clip the reference to the parent def.
    if (scope->canUpdateDefinition(g->name))
    {
-        DefId updated = defArena->freshCell(g->name, g->location, containsSubscriptedDefinition(incomingDef));
+        DefId updated = defArena->freshCell(containsSubscriptedDefinition(incomingDef));
        scope->bindings[g->name] = updated;
        captures[g->name].allVersions.push_back(updated);
        return updated;
@ -1210,10 +1113,10 @@ DefId DataFlowGraphBuilder::visitLValue(AstExprIndexName* i, DefId incomingDef)
 {
    DefId parentDef = visitExpr(i->expr).def;

-    DfgScope* scope = FFlag::LuauDfgScopeStackNotNull ? currentScope() : currentScope_DEPRECATED();
+    DfgScope* scope = currentScope();
    if (scope->canUpdateDefinition(parentDef, i->index.value))
    {
-        DefId updated = defArena->freshCell(i->index, i->location, containsSubscriptedDefinition(incomingDef));
+        DefId updated = defArena->freshCell(containsSubscriptedDefinition(incomingDef));
        scope->props[parentDef][i->index.value] = updated;
        return updated;
    }
@ -1226,12 +1129,12 @@ DefId DataFlowGraphBuilder::visitLValue(AstExprIndexExpr* i, DefId incomingDef)
    DefId parentDef = visitExpr(i->expr).def;
    visitExpr(i->index);

-    DfgScope* scope = FFlag::LuauDfgScopeStackNotNull ? currentScope() : currentScope_DEPRECATED();
+    DfgScope* scope = currentScope();
    if (auto string = i->index->as<AstExprConstantString>())
    {
        if (scope->canUpdateDefinition(parentDef, string->value.data))
        {
-            DefId updated = defArena->freshCell(Symbol{}, i->location, containsSubscriptedDefinition(incomingDef));
+            DefId updated = defArena->freshCell(containsSubscriptedDefinition(incomingDef));
            scope->props[parentDef][string->value.data] = updated;
            return updated;
        }
@ -1239,7 +1142,7 @@ DefId DataFlowGraphBuilder::visitLValue(AstExprIndexExpr* i, DefId incomingDef)
            return visitExpr(static_cast<AstExpr*>(i)).def;
    }
    else
-        return defArena->freshCell(Symbol{}, i->location, /*subscripted=*/true);
+        return defArena->freshCell(/*subscripted=*/true);
 }

 DefId DataFlowGraphBuilder::visitLValue(AstExprError* error, DefId incomingDef)
@ -1257,8 +1160,6 @@ void DataFlowGraphBuilder::visitType(AstType* t)
        return visitType(f);
    else if (auto tyof = t->as<AstTypeTypeof>())
        return visitType(tyof);
-    else if (auto o = t->as<AstTypeOptional>())
-        return;
    else if (auto u = t->as<AstTypeUnion>())
        return visitType(u);
    else if (auto i = t->as<AstTypeIntersection>())
@ -1269,8 +1170,6 @@ void DataFlowGraphBuilder::visitType(AstType* t)
        return; // ok
    else if (auto s = t->as<AstTypeSingletonString>())
        return; // ok
-    else if (auto g = t->as<AstTypeGroup>())
-        return visitType(g->type);
    else
        handle->ice("Unknown AstType in DataFlowGraphBuilder::visitType");
 }
@ -1303,10 +1202,7 @@ void DataFlowGraphBuilder::visitType(AstTypeFunction* f)
    visitGenerics(f->generics);
    visitGenericPacks(f->genericPacks);
    visitTypeList(f->argTypes);
-    if (FFlag::LuauStoreReturnTypesAsPackOnAst)
-        visitTypePack(f->returnTypes);
-    else
-        visitTypeList(f->returnTypes_DEPRECATED);
+    visitTypeList(f->returnTypes);
 }

 void DataFlowGraphBuilder::visitType(AstTypeTypeof* t)
@ -1363,21 +1259,21 @@ void DataFlowGraphBuilder::visitTypeList(AstTypeList l)
        visitTypePack(l.tailType);
 }

-void DataFlowGraphBuilder::visitGenerics(AstArray<AstGenericType*> g)
+void DataFlowGraphBuilder::visitGenerics(AstArray<AstGenericType> g)
 {
-    for (AstGenericType* generic : g)
+    for (AstGenericType generic : g)
    {
-        if (generic->defaultValue)
-            visitType(generic->defaultValue);
+        if (generic.defaultValue)
+            visitType(generic.defaultValue);
    }
 }

-void DataFlowGraphBuilder::visitGenericPacks(AstArray<AstGenericTypePack*> g)
+void DataFlowGraphBuilder::visitGenericPacks(AstArray<AstGenericTypePack> g)
 {
-    for (AstGenericTypePack* generic : g)
+    for (AstGenericTypePack generic : g)
    {
-        if (generic->defaultValue)
-            visitTypePack(generic->defaultValue);
+        if (generic.defaultValue)
+            visitTypePack(generic.defaultValue);
    }
 }

--- a/Analysis/src/Def.cpp
+++ b/Analysis/src/Def.cpp
@ -36,9 +36,9 @@ void collectOperands(DefId def, std::vector<DefId>* operands)
    }
 }

-DefId DefArena::freshCell(Symbol sym, Location location, bool subscripted)
+DefId DefArena::freshCell(bool subscripted)
 {
-    return NotNull{allocator.allocate(Def{Cell{subscripted}, sym, location})};
+    return NotNull{allocator.allocate(Def{Cell{subscripted}})};
 }

 DefId DefArena::phi(DefId a, DefId b)
--- a/Analysis/src/Differ.cpp
+++ b/Analysis/src/Differ.cpp
@ -277,7 +277,7 @@ static DifferResult diffSingleton(DifferEnvironment& env, TypeId left, TypeId ri
 static DifferResult diffFunction(DifferEnvironment& env, TypeId left, TypeId right);
 static DifferResult diffGeneric(DifferEnvironment& env, TypeId left, TypeId right);
 static DifferResult diffNegation(DifferEnvironment& env, TypeId left, TypeId right);
-static DifferResult diffExternType(DifferEnvironment& env, TypeId left, TypeId right);
+static DifferResult diffClass(DifferEnvironment& env, TypeId left, TypeId right);
 struct FindSeteqCounterexampleResult
 {
    // nullopt if no counterexample found
@ -481,14 +481,14 @@ static DifferResult diffNegation(DifferEnvironment& env, TypeId left, TypeId rig
    return differResult;
 }

-static DifferResult diffExternType(DifferEnvironment& env, TypeId left, TypeId right)
+static DifferResult diffClass(DifferEnvironment& env, TypeId left, TypeId right)
 {
-    const ExternType* leftExternType = get<ExternType>(left);
-    const ExternType* rightExternType = get<ExternType>(right);
-    LUAU_ASSERT(leftExternType);
-    LUAU_ASSERT(rightExternType);
+    const ClassType* leftClass = get<ClassType>(left);
+    const ClassType* rightClass = get<ClassType>(right);
+    LUAU_ASSERT(leftClass);
+    LUAU_ASSERT(rightClass);

-    if (leftExternType == rightExternType)
+    if (leftClass == rightClass)
    {
        return DifferResult{};
    }
@ -651,9 +651,9 @@ static DifferResult diffUsingEnv(DifferEnvironment& env, TypeId left, TypeId rig
        {
            return diffNegation(env, left, right);
        }
-        else if (auto lc = get<ExternType>(left))
+        else if (auto lc = get<ClassType>(left))
        {
-            return diffExternType(env, left, right);
+            return diffClass(env, left, right);
        }

        throw InternalCompilerError{"Unimplemented Simple TypeId variant for diffing"};
@ -960,7 +960,7 @@ bool isSimple(TypeId ty)
 {
    ty = follow(ty);
    // TODO: think about GenericType, etc.
-    return get<PrimitiveType>(ty) || get<SingletonType>(ty) || get<AnyType>(ty) || get<NegationType>(ty) || get<ExternType>(ty) ||
+    return get<PrimitiveType>(ty) || get<SingletonType>(ty) || get<AnyType>(ty) || get<NegationType>(ty) || get<ClassType>(ty) ||
           get<UnknownType>(ty) || get<NeverType>(ty);
 }

--- a/Analysis/src/EmbeddedBuiltinDefinitions.cpp
+++ b/Analysis/src/EmbeddedBuiltinDefinitions.cpp
@ -1,12 +1,207 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
 #include "Luau/BuiltinDefinitions.h"

-LUAU_FASTFLAG(LuauDeclareExternType)
-LUAU_FASTFLAG(LuauTypeFunOptional)
+LUAU_FASTFLAGVARIABLE(LuauVectorDefinitionsExtra)
+LUAU_FASTFLAG(LuauBufferBitMethods2)
+LUAU_FASTFLAGVARIABLE(LuauMathMapDefinition)
+LUAU_FASTFLAG(LuauVector2Constructor)

 namespace Luau
 {

+static const std::string kBuiltinDefinitionLuaSrcChecked_DEPRECATED = R"BUILTIN_SRC(
+
+declare bit32: {
+    band: @checked (...number) -> number,
+    bor: @checked (...number) -> number,
+    bxor: @checked (...number) -> number,
+    btest: @checked (number, ...number) -> boolean,
+    rrotate: @checked (x: number, disp: number) -> number,
+    lrotate: @checked (x: number, disp: number) -> number,
+    lshift: @checked (x: number, disp: number) -> number,
+    arshift: @checked (x: number, disp: number) -> number,
+    rshift: @checked (x: number, disp: number) -> number,
+    bnot: @checked (x: number) -> number,
+    extract: @checked (n: number, field: number, width: number?) -> number,
+    replace: @checked (n: number, v: number, field: number, width: number?) -> number,
+    countlz: @checked (n: number) -> number,
+    countrz: @checked (n: number) -> number,
+    byteswap: @checked (n: number) -> number,
+}
+
+declare math: {
+    frexp: @checked (n: number) -> (number, number),
+    ldexp: @checked (s: number, e: number) -> number,
+    fmod: @checked (x: number, y: number) -> number,
+    modf: @checked (n: number) -> (number, number),
+    pow: @checked (x: number, y: number) -> number,
+    exp: @checked (n: number) -> number,
+
+    ceil: @checked (n: number) -> number,
+    floor: @checked (n: number) -> number,
+    abs: @checked (n: number) -> number,
+    sqrt: @checked (n: number) -> number,
+
+    log: @checked (n: number, base: number?) -> number,
+    log10: @checked (n: number) -> number,
+
+    rad: @checked (n: number) -> number,
+    deg: @checked (n: number) -> number,
+
+    sin: @checked (n: number) -> number,
+    cos: @checked (n: number) -> number,
+    tan: @checked (n: number) -> number,
+    sinh: @checked (n: number) -> number,
+    cosh: @checked (n: number) -> number,
+    tanh: @checked (n: number) -> number,
+    atan: @checked (n: number) -> number,
+    acos: @checked (n: number) -> number,
+    asin: @checked (n: number) -> number,
+    atan2: @checked (y: number, x: number) -> number,
+
+    min: @checked (number, ...number) -> number,
+    max: @checked (number, ...number) -> number,
+
+    pi: number,
+    huge: number,
+
+    randomseed: @checked (seed: number) -> (),
+    random: @checked (number?, number?) -> number,
+
+    sign: @checked (n: number) -> number,
+    clamp: @checked (n: number, min: number, max: number) -> number,
+    noise: @checked (x: number, y: number?, z: number?) -> number,
+    round: @checked (n: number) -> number,
+    map: @checked (x: number, inmin: number, inmax: number, outmin: number, outmax: number) -> number,
+}
+
+type DateTypeArg = {
+    year: number,
+    month: number,
+    day: number,
+    hour: number?,
+    min: number?,
+    sec: number?,
+    isdst: boolean?,
+}
+
+type DateTypeResult = {
+    year: number,
+    month: number,
+    wday: number,
+    yday: number,
+    day: number,
+    hour: number,
+    min: number,
+    sec: number,
+    isdst: boolean,
+}
+
+declare os: {
+    time: (time: DateTypeArg?) -> number,
+    date: ((formatString: "*t" | "!*t", time: number?) -> DateTypeResult) & ((formatString: string?, time: number?) -> string),
+    difftime: (t2: DateTypeResult | number, t1: DateTypeResult | number) -> number,
+    clock: () -> number,
+}
+
+@checked declare function require(target: any): any
+
+@checked declare function getfenv(target: any): { [string]: any }
+
+declare _G: any
+declare _VERSION: string
+
+declare function gcinfo(): number
+
+declare function print<T...>(...: T...)
+
+declare function type<T>(value: T): string
+declare function typeof<T>(value: T): string
+
+-- `assert` has a magic function attached that will give more detailed type information
+declare function assert<T>(value: T, errorMessage: string?): T
+declare function error<T>(message: T, level: number?): never
+
+declare function tostring<T>(value: T): string
+declare function tonumber<T>(value: T, radix: number?): number?
+
+declare function rawequal<T1, T2>(a: T1, b: T2): boolean
+declare function rawget<K, V>(tab: {[K]: V}, k: K): V
+declare function rawset<K, V>(tab: {[K]: V}, k: K, v: V): {[K]: V}
+declare function rawlen<K, V>(obj: {[K]: V} | string): number
+
+declare function setfenv<T..., R...>(target: number | (T...) -> R..., env: {[string]: any}): ((T...) -> R...)?
+
+declare function ipairs<V>(tab: {V}): (({V}, number) -> (number?, V), {V}, number)
+
+declare function pcall<A..., R...>(f: (A...) -> R..., ...: A...): (boolean, R...)
+
+-- FIXME: The actual type of `xpcall` is:
+-- <E, A..., R1..., R2...>(f: (A...) -> R1..., err: (E) -> R2..., A...) -> (true, R1...) | (false, R2...)
+-- Since we can't represent the return value, we use (boolean, R1...).
+declare function xpcall<E, A..., R1..., R2...>(f: (A...) -> R1..., err: (E) -> R2..., ...: A...): (boolean, R1...)
+
+-- `select` has a magic function attached to provide more detailed type information
+declare function select<A...>(i: string | number, ...: A...): ...any
+
+-- FIXME: This type is not entirely correct - `loadstring` returns a function or
+-- (nil, string).
+declare function loadstring<A...>(src: string, chunkname: string?): (((A...) -> any)?, string?)
+
+@checked declare function newproxy(mt: boolean?): any
+
+declare coroutine: {
+    create: <A..., R...>(f: (A...) -> R...) -> thread,
+    resume: <A..., R...>(co: thread, A...) -> (boolean, R...),
+    running: () -> thread,
+    status: @checked (co: thread) -> "dead" | "running" | "normal" | "suspended",
+    wrap: <A..., R...>(f: (A...) -> R...) -> ((A...) -> R...),
+    yield: <A..., R...>(A...) -> R...,
+    isyieldable: () -> boolean,
+    close: @checked (co: thread) -> (boolean, any)
+}
+
+declare table: {
+    concat: <V>(t: {V}, sep: string?, i: number?, j: number?) -> string,
+    insert: (<V>(t: {V}, value: V) -> ()) & (<V>(t: {V}, pos: number, value: V) -> ()),
+    maxn: <V>(t: {V}) -> number,
+    remove: <V>(t: {V}, number?) -> V?,
+    sort: <V>(t: {V}, comp: ((V, V) -> boolean)?) -> (),
+    create: <V>(count: number, value: V?) -> {V},
+    find: <V>(haystack: {V}, needle: V, init: number?) -> number?,
+
+    unpack: <V>(list: {V}, i: number?, j: number?) -> ...V,
+    pack: <V>(...V) -> { n: number, [number]: V },
+
+    getn: <V>(t: {V}) -> number,
+    foreach: <K, V>(t: {[K]: V}, f: (K, V) -> ()) -> (),
+    foreachi: <V>({V}, (number, V) -> ()) -> (),
+
+    move: <V>(src: {V}, a: number, b: number, t: number, dst: {V}?) -> {V},
+    clear: <K, V>(table: {[K]: V}) -> (),
+
+    isfrozen: <K, V>(t: {[K]: V}) -> boolean,
+}
+
+declare debug: {
+    info: (<R...>(thread: thread, level: number, options: string) -> R...) & (<R...>(level: number, options: string) -> R...) & (<A..., R1..., R2...>(func: (A...) -> R1..., options: string) -> R2...),
+    traceback: ((message: string?, level: number?) -> string) & ((thread: thread, message: string?, level: number?) -> string),
+}
+
+declare utf8: {
+    char: @checked (...number) -> string,
+    charpattern: string,
+    codes: @checked (str: string) -> ((string, number) -> (number, number), string, number),
+    codepoint: @checked (str: string, i: number?, j: number?) -> ...number,
+    len: @checked (s: string, i: number?, j: number?) -> (number?, number?),
+    offset: @checked (s: string, n: number?, i: number?) -> number,
+}
+
+-- Cannot use `typeof` here because it will produce a polytype when we expect a monotype.
+declare function unpack<V>(tab: {V}, i: number?, j: number?): ...V
+
+)BUILTIN_SRC";
+
 static const std::string kBuiltinDefinitionBaseSrc = R"BUILTIN_SRC(

@checked declare function require(target: any): any
@ -210,7 +405,7 @@ declare table: {
 static const std::string kBuiltinDefinitionDebugSrc = R"BUILTIN_SRC(

 declare debug: {
-    info: ((thread: thread, level: number, options: string) -> ...any) & ((level: number, options: string) -> ...any) & (<A..., R1...>(func: (A...) -> R1..., options: string) -> ...any),
+    info: (<R...>(thread: thread, level: number, options: string) -> R...) & (<R...>(level: number, options: string) -> R...) & (<A..., R1..., R2...>(func: (A...) -> R1..., options: string) -> R2...),
    traceback: ((message: string?, level: number?) -> string) & ((thread: thread, message: string?, level: number?) -> string),
 }

@ -229,6 +424,37 @@ declare utf8: {

 )BUILTIN_SRC";

+static const std::string kBuiltinDefinitionBufferSrc_DEPRECATED = R"BUILTIN_SRC(
+--- Buffer API
+declare buffer: {
+    create: @checked (size: number) -> buffer,
+    fromstring: @checked (str: string) -> buffer,
+    tostring: @checked (b: buffer) -> string,
+    len: @checked (b: buffer) -> number,
+    copy: @checked (target: buffer, targetOffset: number, source: buffer, sourceOffset: number?, count: number?) -> (),
+    fill: @checked (b: buffer, offset: number, value: number, count: number?) -> (),
+    readi8: @checked (b: buffer, offset: number) -> number,
+    readu8: @checked (b: buffer, offset: number) -> number,
+    readi16: @checked (b: buffer, offset: number) -> number,
+    readu16: @checked (b: buffer, offset: number) -> number,
+    readi32: @checked (b: buffer, offset: number) -> number,
+    readu32: @checked (b: buffer, offset: number) -> number,
+    readf32: @checked (b: buffer, offset: number) -> number,
+    readf64: @checked (b: buffer, offset: number) -> number,
+    writei8: @checked (b: buffer, offset: number, value: number) -> (),
+    writeu8: @checked (b: buffer, offset: number, value: number) -> (),
+    writei16: @checked (b: buffer, offset: number, value: number) -> (),
+    writeu16: @checked (b: buffer, offset: number, value: number) -> (),
+    writei32: @checked (b: buffer, offset: number, value: number) -> (),
+    writeu32: @checked (b: buffer, offset: number, value: number) -> (),
+    writef32: @checked (b: buffer, offset: number, value: number) -> (),
+    writef64: @checked (b: buffer, offset: number, value: number) -> (),
+    readstring: @checked (b: buffer, offset: number, count: number) -> string,
+    writestring: @checked (b: buffer, offset: number, value: string, count: number?) -> (),
+}
+
+)BUILTIN_SRC";
+
 static const std::string kBuiltinDefinitionBufferSrc = R"BUILTIN_SRC(
 --- Buffer API
 declare buffer: {
@ -262,15 +488,36 @@ declare buffer: {

 )BUILTIN_SRC";

-static const std::string kBuiltinDefinitionVectorSrc = (FFlag::LuauDeclareExternType)
-    ? R"BUILTIN_SRC(
+static const std::string kBuiltinDefinitionVectorSrc_NoExtra_NoVector2Ctor_DEPRECATED = R"BUILTIN_SRC(

-- While vector would have been better represented as a built-in primitive type, type solver extern type handling covers most of the properties
-declare extern type vector with
-    x: number
-    y: number
-    z: number
-end
+-- TODO: this will be replaced with a built-in primitive type
+declare class vector end
+
+declare vector: {
+    create: @checked (x: number, y: number, z: number) -> vector,
+    magnitude: @checked (vec: vector) -> number,
+    normalize: @checked (vec: vector) -> vector,
+    cross: @checked (vec1: vector, vec2: vector) -> vector,
+    dot: @checked (vec1: vector, vec2: vector) -> number,
+    angle: @checked (vec1: vector, vec2: vector, axis: vector?) -> number,
+    floor: @checked (vec: vector) -> vector,
+    ceil: @checked (vec: vector) -> vector,
+    abs: @checked (vec: vector) -> vector,
+    sign: @checked (vec: vector) -> vector,
+    clamp: @checked (vec: vector, min: vector, max: vector) -> vector,
+    max: @checked (vector, ...vector) -> vector,
+    min: @checked (vector, ...vector) -> vector,
+
+    zero: vector,
+    one: vector,
+}
+
+)BUILTIN_SRC";
+
+static const std::string kBuiltinDefinitionVectorSrc_NoExtra_DEPRECATED = R"BUILTIN_SRC(
+
+-- TODO: this will be replaced with a built-in primitive type
+declare class vector end

 declare vector: {
    create: @checked (x: number, y: number, z: number?) -> vector,
@ -291,8 +538,39 @@ declare vector: {
    one: vector,
 }

-)BUILTIN_SRC"
-    : R"BUILTIN_SRC(
+)BUILTIN_SRC";
+
+static const std::string kBuiltinDefinitionVectorSrc_NoVector2Ctor_DEPRECATED = R"BUILTIN_SRC(
+
+-- While vector would have been better represented as a built-in primitive type, type solver class handling covers most of the properties
+declare class vector
+    x: number
+    y: number
+    z: number
+end
+
+declare vector: {
+    create: @checked (x: number, y: number, z: number) -> vector,
+    magnitude: @checked (vec: vector) -> number,
+    normalize: @checked (vec: vector) -> vector,
+    cross: @checked (vec1: vector, vec2: vector) -> vector,
+    dot: @checked (vec1: vector, vec2: vector) -> number,
+    angle: @checked (vec1: vector, vec2: vector, axis: vector?) -> number,
+    floor: @checked (vec: vector) -> vector,
+    ceil: @checked (vec: vector) -> vector,
+    abs: @checked (vec: vector) -> vector,
+    sign: @checked (vec: vector) -> vector,
+    clamp: @checked (vec: vector, min: vector, max: vector) -> vector,
+    max: @checked (vector, ...vector) -> vector,
+    min: @checked (vector, ...vector) -> vector,
+
+    zero: vector,
+    one: vector,
+}
+
+)BUILTIN_SRC";
+
+static const std::string kBuiltinDefinitionVectorSrc = R"BUILTIN_SRC(

 -- While vector would have been better represented as a built-in primitive type, type solver class handling covers most of the properties
 declare class vector
@ -324,132 +602,35 @@ declare vector: {

 std::string getBuiltinDefinitionSource()
 {
-    std::string result = kBuiltinDefinitionBaseSrc;
+    std::string result = FFlag::LuauMathMapDefinition ? kBuiltinDefinitionBaseSrc : kBuiltinDefinitionLuaSrcChecked_DEPRECATED;

-    result += kBuiltinDefinitionBit32Src;
-    result += kBuiltinDefinitionMathSrc;
-    result += kBuiltinDefinitionOsSrc;
-    result += kBuiltinDefinitionCoroutineSrc;
-    result += kBuiltinDefinitionTableSrc;
-    result += kBuiltinDefinitionDebugSrc;
-    result += kBuiltinDefinitionUtf8Src;
-    result += kBuiltinDefinitionBufferSrc;
-    result += kBuiltinDefinitionVectorSrc;
+    if (FFlag::LuauMathMapDefinition)
+    {
+        result += kBuiltinDefinitionBit32Src;
+        result += kBuiltinDefinitionMathSrc;
+        result += kBuiltinDefinitionOsSrc;
+        result += kBuiltinDefinitionCoroutineSrc;
+        result += kBuiltinDefinitionTableSrc;
+        result += kBuiltinDefinitionDebugSrc;
+        result += kBuiltinDefinitionUtf8Src;
+    }

-    return result;
-}
+    result += FFlag::LuauBufferBitMethods2 ? kBuiltinDefinitionBufferSrc : kBuiltinDefinitionBufferSrc_DEPRECATED;

-// TODO: split into separate tagged unions when the new solver can appropriately handle that.
-static const std::string kBuiltinDefinitionTypeMethodSrc = R"BUILTIN_SRC(
-
-export type type = {
-    tag: "nil" | "unknown" | "never" | "any" | "boolean" | "number" | "string" | "buffer" | "thread" |
-         "singleton" | "negation" | "union" | "intersection" | "table" | "function" | "class" | "generic",
-
-    is: (self: type, arg: string) -> boolean,
-
-    -- for singleton type
-    value: (self: type) -> (string | boolean | nil),
-
-    -- for negation type
-    inner: (self: type) -> type,
-
-    -- for union and intersection types
-    components: (self: type) -> {type},
-
-    -- for table type
-    setproperty: (self: type, key: type, value: type?) -> (),
-    setreadproperty: (self: type, key: type, value: type?) -> (),
-    setwriteproperty: (self: type, key: type, value: type?) -> (),
-    readproperty: (self: type, key: type) -> type?,
-    writeproperty: (self: type, key: type) -> type?,
-    properties: (self: type) -> { [type]: { read: type?, write: type? } },
-    setindexer: (self: type, index: type, result: type) -> (),
-    setreadindexer: (self: type, index: type, result: type) -> (),
-    setwriteindexer: (self: type, index: type, result: type) -> (),
-    indexer: (self: type) -> { index: type, readresult: type, writeresult: type }?,
-    readindexer: (self: type) -> { index: type, result: type }?,
-    writeindexer: (self: type) -> { index: type, result: type }?,
-    setmetatable: (self: type, arg: type) -> (),
-    metatable: (self: type) -> type?,
-
-    -- for function type
-    setparameters: (self: type, head: {type}?, tail: type?) -> (),
-    parameters: (self: type) -> { head: {type}?, tail: type? },
-    setreturns: (self: type, head: {type}?, tail: type? ) -> (),
-    returns: (self: type) -> { head: {type}?, tail: type? },
-    setgenerics: (self: type, {type}?) -> (),
-    generics: (self: type) -> {type},
-
-    -- for class type
-    -- 'properties', 'metatable', 'indexer', 'readindexer' and 'writeindexer' are shared with table type
-    readparent: (self: type) -> type?,
-    writeparent: (self: type) -> type?,
-
-    -- for generic type
-    name: (self: type) -> string?,
-    ispack: (self: type) -> boolean,
-}
-
-)BUILTIN_SRC";
-
-static const std::string kBuiltinDefinitionTypesLibSrc = R"BUILTIN_SRC(
-
-declare types: {
-    unknown: type,
-    never: type,
-    any: type,
-    boolean: type,
-    number: type,
-    string: type,
-    thread: type,
-    buffer: type,
-
-    singleton: @checked (arg: string | boolean | nil) -> type,
-    generic: @checked (name: string, ispack: boolean?) -> type,
-    negationof: @checked (arg: type) -> type,
-    unionof: @checked (...type) -> type,
-    intersectionof: @checked (...type) -> type,
-    newtable: @checked (props: {[type]: type} | {[type]: { read: type, write: type } } | nil, indexer: { index: type, readresult: type, writeresult: type }?, metatable: type?) -> type,
-    newfunction: @checked (parameters: { head: {type}?, tail: type? }?, returns: { head: {type}?, tail: type? }?, generics: {type}?) -> type,
-    copy: @checked (arg: type) -> type,
-}
-)BUILTIN_SRC";
-
-static const std::string kBuiltinDefinitionTypesLibWithOptionalSrc = R"BUILTIN_SRC(
-
-declare types: {
-    unknown: type,
-    never: type,
-    any: type,
-    boolean: type,
-    number: type,
-    string: type,
-    thread: type,
-    buffer: type,
-
-    singleton: @checked (arg: string | boolean | nil) -> type,
-    optional: @checked (arg: type) -> type,
-    generic: @checked (name: string, ispack: boolean?) -> type,
-    negationof: @checked (arg: type) -> type,
-    unionof: @checked (...type) -> type,
-    intersectionof: @checked (...type) -> type,
-    newtable: @checked (props: {[type]: type} | {[type]: { read: type, write: type } } | nil, indexer: { index: type, readresult: type, writeresult: type }?, metatable: type?) -> type,
-    newfunction: @checked (parameters: { head: {type}?, tail: type? }?, returns: { head: {type}?, tail: type? }?, generics: {type}?) -> type,
-    copy: @checked (arg: type) -> type,
-}
-)BUILTIN_SRC";
-
-
-std::string getTypeFunctionDefinitionSource()
-{
-
-    std::string result = kBuiltinDefinitionTypeMethodSrc;
-
-    if (FFlag::LuauTypeFunOptional)
-        result += kBuiltinDefinitionTypesLibWithOptionalSrc;
+    if (FFlag::LuauVectorDefinitionsExtra)
+    {
+        if (FFlag::LuauVector2Constructor)
+            result += kBuiltinDefinitionVectorSrc;
+        else
+            result += kBuiltinDefinitionVectorSrc_NoVector2Ctor_DEPRECATED;
+    }
    else
-        result += kBuiltinDefinitionTypesLibSrc;
+    {
+        if (FFlag::LuauVector2Constructor)
+            result += kBuiltinDefinitionVectorSrc_NoExtra_DEPRECATED;
+        else
+            result += kBuiltinDefinitionVectorSrc_NoExtra_NoVector2Ctor_DEPRECATED;
+    }

    return result;
 }
--- a/Analysis/src/EqSatSimplification.cpp
+++ b/Analysis/src/EqSatSimplification.cpp
@ -92,24 +92,18 @@ size_t TTable::Hash::operator()(const TTable& value) const
    return hash;
 }

-StringId StringCache::add(std::string_view s)
+uint32_t StringCache::add(std::string_view s)
 {
-    /* Important subtlety: This use of DenseHashMap<std::string_view, StringId>
-     * is okay because std::hash<std::string_view> works solely on the bytes
-     * referred by the string_view.
-     *
-     * In other words, two string views which contain the same bytes will have
-     * the same hash whether or not their addresses are the same.
-     */
-    if (StringId* it = strings.find(s))
+    size_t hash = std::hash<std::string_view>()(s);
+    if (uint32_t* it = strings.find(hash))
        return *it;

    char* storage = static_cast<char*>(allocator.allocate(s.size()));
    memcpy(storage, s.data(), s.size());

-    StringId result = StringId(views.size());
+    uint32_t result = uint32_t(views.size());
    views.emplace_back(storage, s.size());
-    strings[s] = result;
+    strings[hash] = result;
    return result;
 }

@ -330,9 +324,9 @@ Id toId(
        return egraph.add(TOpaque{ty});
    else if (get<FunctionType>(ty))
        return egraph.add(TFunction{ty});
-    else if (ty == builtinTypes->externType)
+    else if (ty == builtinTypes->classType)
        return egraph.add(TTopClass{});
-    else if (get<ExternType>(ty))
+    else if (get<ClassType>(ty))
        return egraph.add(TClass{ty});
    else if (get<AnyType>(ty))
        return egraph.add(TAny{});
@ -396,17 +390,6 @@ Id toId(
    {
        LUAU_ASSERT(tfun->packArguments.empty());

-        if (tfun->userFuncName)
-        {
-            // TODO: User defined type functions are pseudo-effectful: error
-            // reporting is done via the `print` statement, so running a
-            // UDTF multiple times may end up double erroring. egraphs
-            // currently may induce type functions to be reduced multiple
-            // times. We should probably opt _not_ to process user defined
-            // type functions at all.
-            return egraph.add(TOpaque{ty});
-        }
-
        std::vector<Id> parts;
        parts.reserve(tfun->typeArguments.size());
        for (TypeId part : tfun->typeArguments)
@ -752,7 +735,7 @@ TypeId fromId(
    else if (node.get<TTopTable>())
        return builtinTypes->tableType;
    else if (node.get<TTopClass>())
-        return builtinTypes->externType;
+        return builtinTypes->classType;
    else if (node.get<TBuffer>())
        return builtinTypes->bufferType;
    else if (auto opaque = node.get<TOpaque>())
@ -1007,7 +990,7 @@ static std::string getNodeName(const StringCache& strings, const EType& node)
        return "\xe2\x88\xa9";
    else if (auto cls = node.get<TClass>())
    {
-        const ExternType* ct = get<ExternType>(cls->value());
+        const ClassType* ct = get<ClassType>(cls->value());
        LUAU_ASSERT(ct);
        return ct->name;
    }
@ -1177,12 +1160,12 @@ enum SubclassRelationship

 static SubclassRelationship relateClasses(const TClass* leftClass, const TClass* rightClass)
 {
-    const ExternType* leftExternType = Luau::get<ExternType>(leftClass->value());
-    const ExternType* rightExternType = Luau::get<ExternType>(rightClass->value());
+    const ClassType* leftClassType = Luau::get<ClassType>(leftClass->value());
+    const ClassType* rightClassType = Luau::get<ClassType>(rightClass->value());

-    if (isSubclass(leftExternType, rightExternType))
+    if (isSubclass(leftClassType, rightClassType))
        return RightSuper;
-    else if (isSubclass(rightExternType, leftExternType))
+    else if (isSubclass(rightClassType, leftClassType))
        return LeftSuper;
    else
        return Unrelated;
--- a/Analysis/src/Error.cpp
+++ b/Analysis/src/Error.cpp
@ -8,7 +8,6 @@
 #include "Luau/StringUtils.h"
 #include "Luau/ToString.h"
 #include "Luau/Type.h"
-#include "Luau/TypeChecker2.h"
 #include "Luau/TypeFunction.h"

 #include <optional>
@ -18,7 +17,6 @@
 #include <unordered_set>

 LUAU_FASTINTVARIABLE(LuauIndentTypeMismatchMaxTypeLength, 10)
-LUAU_FASTFLAG(DebugLuauGreedyGeneralization)

 static std::string wrongNumberOfArgsString(
    size_t expectedCount,
@ -70,7 +68,7 @@ namespace Luau
 {

 // this list of binary operator type functions is used for better stringification of type functions errors
-static const std::unordered_map<std::string, const char*> DEPRECATED_kBinaryOps{
+static const std::unordered_map<std::string, const char*> kBinaryOps{
    {"add", "+"},
    {"sub", "-"},
    {"mul", "*"},
@ -86,27 +84,12 @@ static const std::unordered_map<std::string, const char*> DEPRECATED_kBinaryOps{
    {"eq", "== or ~="}
 };

-static const std::unordered_map<std::string, const char*> kBinaryOps{
-    {"add", "+"},
-    {"sub", "-"},
-    {"mul", "*"},
-    {"div", "/"},
-    {"idiv", "//"},
-    {"pow", "^"},
-    {"mod", "%"},
-    {"concat", ".."},
-    {"lt", "< or >="},
-    {"le", "<= or >"},
-    {"eq", "== or ~="}
-};
-
 // this list of unary operator type functions is used for better stringification of type functions errors
 static const std::unordered_map<std::string, const char*> kUnaryOps{{"unm", "-"}, {"len", "#"}, {"not", "not"}};

 // this list of type functions will receive a special error indicating that the user should file a bug on the GitHub repository
 // putting a type function in this list indicates that it is expected to _always_ reduce
-static const std::unordered_set<std::string> DEPRECATED_kUnreachableTypeFunctions{"refine", "singleton", "union", "intersect"};
-static const std::unordered_set<std::string> kUnreachableTypeFunctions{"refine", "singleton", "union", "intersect", "and", "or"};
+static const std::unordered_set<std::string> kUnreachableTypeFunctions{"refine", "singleton", "union", "intersect"};

 struct ErrorConverter
 {
@ -133,10 +116,7 @@ struct ErrorConverter
            size_t luauIndentTypeMismatchMaxTypeLength = size_t(FInt::LuauIndentTypeMismatchMaxTypeLength);
            if (givenType.length() <= luauIndentTypeMismatchMaxTypeLength || wantedType.length() <= luauIndentTypeMismatchMaxTypeLength)
                return "Type " + given + " could not be converted into " + wanted;
-            if (FFlag::LuauImproveTypePathsInErrors)
-                return "Type\n\t" + given + "\ncould not be converted into\n\t" + wanted;
-            else
-                return "Type\n    " + given + "\ncould not be converted into\n    " + wanted;
+            return "Type\n    " + given + "\ncould not be converted into\n    " + wanted;
        };

        if (givenTypeName == wantedTypeName)
@ -203,7 +183,7 @@ struct ErrorConverter
        TypeId t = follow(e.table);
        if (get<TableType>(t))
            return "Key '" + e.key + "' not found in table '" + Luau::toString(t) + "'";
-        else if (get<ExternType>(t))
+        else if (get<ClassType>(t))
            return "Key '" + e.key + "' not found in class '" + Luau::toString(t) + "'";
        else
            return "Type '" + Luau::toString(e.table) + "' does not have key '" + e.key + "'";
@ -371,7 +351,7 @@ struct ErrorConverter
        std::string s = "Key '" + e.key + "' not found in ";

        TypeId t = follow(e.table);
-        if (get<ExternType>(t))
+        if (get<ClassType>(t))
            s += "class";
        else
            s += "table";
@ -402,8 +382,8 @@ struct ErrorConverter
        std::optional<TypeId> metatable;
        if (const MetatableType* mtType = get<MetatableType>(type))
            metatable = mtType->metatable;
-        else if (const ExternType* externType = get<ExternType>(type))
-            metatable = externType->metatable;
+        else if (const ClassType* classType = get<ClassType>(type))
+            metatable = classType->metatable;

        if (!metatable)
            return std::nullopt;
@ -611,7 +591,7 @@ struct ErrorConverter
        return ss;
    }

-    std::string operator()(const DynamicPropertyLookupOnExternTypesUnsafe& e) const
+    std::string operator()(const DynamicPropertyLookupOnClassesUnsafe& e) const
    {
        return "Attempting a dynamic property access on type '" + Luau::toString(e.ty) + "' is unsafe and may cause exceptions at runtime";
    }
@ -621,7 +601,7 @@ struct ErrorConverter
        auto tfit = get<TypeFunctionInstanceType>(e.ty);
        LUAU_ASSERT(tfit); // Luau analysis has actually done something wrong if this type is not a type function.
        if (!tfit)
-            return "Internal error: Unexpected type " + Luau::toString(e.ty) + " flagged as an uninhabited type function.";
+            return "Unexpected type " + Luau::toString(e.ty) + " flagged as an uninhabited type function.";

        // unary operators
        if (auto unaryString = kUnaryOps.find(tfit->function->name); unaryString != kUnaryOps.end())
@ -658,8 +638,7 @@ struct ErrorConverter
        }

        // binary operators
-        const auto binaryOps = FFlag::DebugLuauGreedyGeneralization ? kBinaryOps : DEPRECATED_kBinaryOps;
-        if (auto binaryString = binaryOps.find(tfit->function->name); binaryString != binaryOps.end())
+        if (auto binaryString = kBinaryOps.find(tfit->function->name); binaryString != kBinaryOps.end())
        {
            std::string result = "Operator '" + std::string(binaryString->second) + "' could not be applied to operands of types ";

@ -713,10 +692,10 @@ struct ErrorConverter
                       "'";
        }

-        if ((FFlag::DebugLuauGreedyGeneralization ? kUnreachableTypeFunctions : DEPRECATED_kUnreachableTypeFunctions).count(tfit->function->name))
+        if (kUnreachableTypeFunctions.count(tfit->function->name))
        {
            return "Type function instance " + Luau::toString(e.ty) + " is uninhabited\n" +
-                "This is likely to be a bug, please report it at https://github.com/luau-lang/luau/issues";
+                   "This is likely to be a bug, please report it at https://github.com/luau-lang/luau/issues";
        }

        // Everything should be specialized above to report a more descriptive error that hopefully does not mention "type functions" explicitly.
@ -772,15 +751,8 @@ struct ErrorConverter

    std::string operator()(const NonStrictFunctionDefinitionError& e) const
    {
-        if (e.functionName.empty())
-        {
-            return "Argument " + e.argument + " with type '" + toString(e.argumentType) + "' is used in a way that will run time error";
-        }
-        else
-        {
-            return "Argument " + e.argument + " with type '" + toString(e.argumentType) + "' in function '" + e.functionName +
-                   "' is used in a way that will run time error";
-        }
+        return "Argument " + e.argument + " with type '" + toString(e.argumentType) + "' in function '" + e.functionName +
+               "' is used in a way that will run time error";
    }

    std::string operator()(const PropertyAccessViolation& e) const
@ -819,11 +791,6 @@ struct ErrorConverter
        return e.message;
    }

-    std::string operator()(const ReservedIdentifier& e) const
-    {
-        return e.name + " cannot be used as an identifier for a type function or alias";
-    }
-
    std::string operator()(const CannotAssignToNever& e) const
    {
        std::string result = "Cannot assign a value of type " + toString(e.rhsType) + " to a field of type never";
@ -1149,7 +1116,7 @@ bool TypePackMismatch::operator==(const TypePackMismatch& rhs) const
    return *wantedTp == *rhs.wantedTp && *givenTp == *rhs.givenTp;
 }

-bool DynamicPropertyLookupOnExternTypesUnsafe::operator==(const DynamicPropertyLookupOnExternTypesUnsafe& rhs) const
+bool DynamicPropertyLookupOnClassesUnsafe::operator==(const DynamicPropertyLookupOnClassesUnsafe& rhs) const
 {
    return ty == rhs.ty;
 }
@ -1211,11 +1178,6 @@ bool UserDefinedTypeFunctionError::operator==(const UserDefinedTypeFunctionError
    return message == rhs.message;
 }

-bool ReservedIdentifier::operator==(const ReservedIdentifier& rhs) const
-{
-    return name == rhs.name;
-}
-
 bool CannotAssignToNever::operator==(const CannotAssignToNever& rhs) const
 {
    if (cause.size() != rhs.cause.size())
@ -1391,7 +1353,7 @@ void copyError(T& e, TypeArena& destArena, CloneState& cloneState)
        e.wantedTp = clone(e.wantedTp);
        e.givenTp = clone(e.givenTp);
    }
-    else if constexpr (std::is_same_v<T, DynamicPropertyLookupOnExternTypesUnsafe>)
+    else if constexpr (std::is_same_v<T, DynamicPropertyLookupOnClassesUnsafe>)
        e.ty = clone(e.ty);
    else if constexpr (std::is_same_v<T, UninhabitedTypeFunction>)
        e.ty = clone(e.ty);
@ -1435,9 +1397,6 @@ void copyError(T& e, TypeArena& destArena, CloneState& cloneState)
        for (auto& ty : e.cause)
            ty = clone(ty);
    }
-    else if constexpr (std::is_same_v<T, ReservedIdentifier>)
-    {
-    }
    else
        static_assert(always_false_v<T>, "Non-exhaustive type switch");
 }
--- a/Analysis/src/FileResolver.cpp
+++ b/Analysis/src/FileResolver.cpp
@ -1,160 +0,0 @@
-// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
-#include "Luau/FileResolver.h"
-
-#include "Luau/Common.h"
-#include "Luau/StringUtils.h"
-
-#include <algorithm>
-#include <memory>
-#include <optional>
-#include <string_view>
-#include <utility>
-
-namespace Luau
-{
-
-static std::optional<RequireSuggestions> processRequireSuggestions(std::optional<RequireSuggestions> suggestions)
-{
-    if (!suggestions)
-        return suggestions;
-
-    for (RequireSuggestion& suggestion : *suggestions)
-    {
-        suggestion.fullPath = escape(suggestion.fullPath);
-    }
-
-    return suggestions;
-}
-
-static RequireSuggestions makeSuggestionsFromAliases(std::vector<RequireAlias> aliases)
-{
-    RequireSuggestions result;
-    for (RequireAlias& alias : aliases)
-    {
-        RequireSuggestion suggestion;
-        suggestion.label = "@" + std::move(alias.alias);
-        suggestion.fullPath = suggestion.label;
-        suggestion.tags = std::move(alias.tags);
-        result.push_back(std::move(suggestion));
-    }
-    return result;
-}
-
-static RequireSuggestions makeSuggestionsForFirstComponent(std::unique_ptr<RequireNode> node)
-{
-    RequireSuggestions result = makeSuggestionsFromAliases(node->getAvailableAliases());
-    result.push_back(RequireSuggestion{"./", "./", {}});
-    result.push_back(RequireSuggestion{"../", "../", {}});
-    return result;
-}
-
-static RequireSuggestions makeSuggestionsFromNode(std::unique_ptr<RequireNode> node, const std::string_view path, bool isPartialPath)
-{
-    LUAU_ASSERT(!path.empty());
-
-    RequireSuggestions result;
-
-    const size_t lastSlashInPath = path.find_last_of('/');
-
-    if (lastSlashInPath != std::string_view::npos)
-    {
-        // Add a suggestion for the parent directory
-        RequireSuggestion parentSuggestion;
-        parentSuggestion.label = "..";
-
-        // TODO: after exposing require-by-string's path normalization API, this
-        // if-else can be replaced. Instead, we can simply normalize the result
-        // of inserting ".." at the end of the current path.
-        if (lastSlashInPath >= 2 && path.substr(lastSlashInPath - 2, 3) == "../")
-        {
-            parentSuggestion.fullPath = path.substr(0, lastSlashInPath + 1);
-            parentSuggestion.fullPath += "..";
-        }
-        else
-        {
-            parentSuggestion.fullPath = path.substr(0, lastSlashInPath);
-        }
-
-        result.push_back(std::move(parentSuggestion));
-    }
-
-    std::string fullPathPrefix;
-    if (isPartialPath)
-    {
-        // ./path/to/chi -> ./path/to/
-        fullPathPrefix += path.substr(0, lastSlashInPath + 1);
-    }
-    else
-    {
-        if (path.back() == '/')
-        {
-            // ./path/to/ -> ./path/to/
-            fullPathPrefix += path;
-        }
-        else
-        {
-            // ./path/to -> ./path/to/
-            fullPathPrefix += path;
-            fullPathPrefix += "/";
-        }
-    }
-
-    for (const std::unique_ptr<RequireNode>& child : node->getChildren())
-    {
-        if (!child)
-            continue;
-
-        std::string pathComponent = child->getPathComponent();
-
-        // If path component contains a slash, it cannot be required by string.
-        // There's no point suggesting it.
-        if (pathComponent.find('/') != std::string::npos)
-            continue;
-
-        RequireSuggestion suggestion;
-        suggestion.label = isPartialPath || path.back() == '/' ? child->getLabel() : "/" + child->getLabel();
-        suggestion.fullPath = fullPathPrefix + std::move(pathComponent);
-        suggestion.tags = child->getTags();
-        result.push_back(std::move(suggestion));
-    }
-
-    return result;
-}
-
-std::optional<RequireSuggestions> RequireSuggester::getRequireSuggestionsImpl(const ModuleName& requirer, const std::optional<std::string>& path)
-    const
-{
-    if (!path)
-        return std::nullopt;
-
-    std::unique_ptr<RequireNode> requirerNode = getNode(requirer);
-    if (!requirerNode)
-        return std::nullopt;
-
-    const size_t slashPos = path->find_last_of('/');
-
-    if (slashPos == std::string::npos)
-        return makeSuggestionsForFirstComponent(std::move(requirerNode));
-
-    // If path already points at a Node, return the Node's children as paths.
-    if (std::unique_ptr<RequireNode> node = requirerNode->resolvePathToNode(*path))
-        return makeSuggestionsFromNode(std::move(node), *path, /* isPartialPath = */ false);
-
-    // Otherwise, recover a partial path and use this to generate suggestions.
-    if (std::unique_ptr<RequireNode> partialNode = requirerNode->resolvePathToNode(path->substr(0, slashPos)))
-        return makeSuggestionsFromNode(std::move(partialNode), *path, /* isPartialPath = */ true);
-
-    return std::nullopt;
-}
-
-std::optional<RequireSuggestions> RequireSuggester::getRequireSuggestions(const ModuleName& requirer, const std::optional<std::string>& path) const
-{
-    return processRequireSuggestions(getRequireSuggestionsImpl(requirer, path));
-}
-
-std::optional<RequireSuggestions> FileResolver::getRequireSuggestions(const ModuleName& requirer, const std::optional<std::string>& path) const
-{
-    return requireSuggester ? requireSuggester->getRequireSuggestions(requirer, path) : std::nullopt;
-}
-
-} // namespace Luau
--- a/Analysis/src/FragmentAutocomplete.cpp
+++ b/Analysis/src/FragmentAutocomplete.cpp
--- a/Analysis/src/Frontend.cpp
+++ b/Analysis/src/Frontend.cpp
@ -1,6 +1,7 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
 #include "Luau/Frontend.h"

+#include "Luau/AnyTypeSummary.h"
 #include "Luau/BuiltinDefinitions.h"
 #include "Luau/Clone.h"
 #include "Luau/Common.h"
@ -38,16 +39,19 @@ LUAU_FASTINT(LuauTypeInferRecursionLimit)
 LUAU_FASTINT(LuauTarjanChildLimit)
 LUAU_FASTFLAG(LuauInferInNoCheckMode)
 LUAU_FASTFLAGVARIABLE(LuauKnowsTheDataModel3)
+LUAU_FASTFLAGVARIABLE(LuauStoreCommentsForDefinitionFiles)
 LUAU_FASTFLAG(LuauSolverV2)
-LUAU_DYNAMIC_FASTFLAGVARIABLE(LuauRethrowKnownExceptions, false)
-LUAU_FASTFLAG(DebugLuauGreedyGeneralization)
 LUAU_FASTFLAGVARIABLE(DebugLuauLogSolverToJson)
 LUAU_FASTFLAGVARIABLE(DebugLuauLogSolverToJsonFile)
 LUAU_FASTFLAGVARIABLE(DebugLuauForbidInternalTypes)
 LUAU_FASTFLAGVARIABLE(DebugLuauForceStrictMode)
 LUAU_FASTFLAGVARIABLE(DebugLuauForceNonStrictMode)
+LUAU_DYNAMIC_FASTFLAGVARIABLE(LuauRunCustomModuleChecks, false)

-LUAU_FASTFLAG(LuauTypeFunResultInAutocomplete)
+LUAU_FASTFLAG(StudioReportLuauAny2)
+LUAU_FASTFLAGVARIABLE(LuauStoreSolverTypeOnModule)
+
+LUAU_FASTFLAGVARIABLE(LuauReferenceAllocatorInNewSolver)

 namespace Luau
 {
@ -77,20 +81,6 @@ struct BuildQueueItem
    Frontend::Stats stats;
 };

-struct BuildQueueWorkState
-{
-    std::function<void(std::function<void()> task)> executeTask;
-
-    std::vector<BuildQueueItem> buildQueueItems;
-
-    std::mutex mtx;
-    std::condition_variable cv;
-    std::vector<size_t> readyQueueItems;
-
-    size_t processing = 0;
-    size_t remaining = 0;
-};
-
 std::optional<Mode> parseMode(const std::vector<HotComment>& hotcomments)
 {
    for (const HotComment& hc : hotcomments)
@ -129,9 +119,9 @@ static void generateDocumentationSymbols(TypeId ty, const std::string& rootName)
            prop.documentationSymbol = rootName + "." + name;
        }
    }
-    else if (ExternType* etv = getMutable<ExternType>(ty))
+    else if (ClassType* ctv = getMutable<ClassType>(ty))
    {
-        for (auto& [name, prop] : etv->props)
+        for (auto& [name, prop] : ctv->props)
        {
            prop.documentationSymbol = rootName + "." + name;
        }
@ -148,7 +138,7 @@ static ParseResult parseSourceForModule(std::string_view source, Luau::SourceMod
    sourceModule.root = parseResult.root;
    sourceModule.mode = Mode::Definition;

-    if (options.captureComments)
+    if (FFlag::LuauStoreCommentsForDefinitionFiles && options.captureComments)
    {
        sourceModule.hotcomments = parseResult.hotcomments;
        sourceModule.commentLocations = parseResult.commentLocations;
@ -455,6 +445,20 @@ CheckResult Frontend::check(const ModuleName& name, std::optional<FrontendOption

        if (item.name == name)
            checkResult.lintResult = item.module->lintResult;
+
+        if (FFlag::StudioReportLuauAny2 && item.options.retainFullTypeGraphs)
+        {
+            if (item.module)
+            {
+                const SourceModule& sourceModule = *item.sourceModule;
+                if (sourceModule.mode == Luau::Mode::Strict)
+                {
+                    item.module->ats.root = toString(sourceModule.root);
+                }
+                item.module->ats.rootSrc = sourceModule.root;
+                item.module->ats.traverse(item.module.get(), sourceModule.root, NotNull{&builtinTypes_});
+            }
+        }
    }

    return checkResult;
@ -485,8 +489,7 @@ std::vector<ModuleName> Frontend::checkQueuedModules(
    std::swap(currModuleQueue, moduleQueue);

    DenseHashSet<Luau::ModuleName> seen{{}};
-
-    std::shared_ptr<BuildQueueWorkState> state = std::make_shared<BuildQueueWorkState>();
+    std::vector<BuildQueueItem> buildQueueItems;

    for (const ModuleName& name : currModuleQueue)
    {
@ -510,18 +513,18 @@ std::vector<ModuleName> Frontend::checkQueuedModules(
            }
        );

-        addBuildQueueItems(state->buildQueueItems, queue, cycleDetected, seen, frontendOptions);
+        addBuildQueueItems(buildQueueItems, queue, cycleDetected, seen, frontendOptions);
    }

-    if (state->buildQueueItems.empty())
+    if (buildQueueItems.empty())
        return {};

    // We need a mapping from modules to build queue slots
    std::unordered_map<ModuleName, size_t> moduleNameToQueue;

-    for (size_t i = 0; i < state->buildQueueItems.size(); i++)
+    for (size_t i = 0; i < buildQueueItems.size(); i++)
    {
-        BuildQueueItem& item = state->buildQueueItems[i];
+        BuildQueueItem& item = buildQueueItems[i];
        moduleNameToQueue[item.name] = i;
    }

@ -534,13 +537,67 @@ std::vector<ModuleName> Frontend::checkQueuedModules(
        };
    }

-    state->executeTask = executeTask;
-    state->remaining = state->buildQueueItems.size();
+    std::mutex mtx;
+    std::condition_variable cv;
+    std::vector<size_t> readyQueueItems;

-    // Record dependencies between modules
-    for (size_t i = 0; i < state->buildQueueItems.size(); i++)
+    size_t processing = 0;
+    size_t remaining = buildQueueItems.size();
+
+    auto itemTask = [&](size_t i)
    {
-        BuildQueueItem& item = state->buildQueueItems[i];
+        BuildQueueItem& item = buildQueueItems[i];
+
+        try
+        {
+            checkBuildQueueItem(item);
+        }
+        catch (...)
+        {
+            item.exception = std::current_exception();
+        }
+
+        {
+            std::unique_lock guard(mtx);
+            readyQueueItems.push_back(i);
+        }
+
+        cv.notify_one();
+    };
+
+    auto sendItemTask = [&](size_t i)
+    {
+        BuildQueueItem& item = buildQueueItems[i];
+
+        item.processing = true;
+        processing++;
+
+        executeTask(
+            [&itemTask, i]()
+            {
+                itemTask(i);
+            }
+        );
+    };
+
+    auto sendCycleItemTask = [&]
+    {
+        for (size_t i = 0; i < buildQueueItems.size(); i++)
+        {
+            BuildQueueItem& item = buildQueueItems[i];
+
+            if (!item.processing)
+            {
+                sendItemTask(i);
+                break;
+            }
+        }
+    };
+
+    // In a first pass, check modules that have no dependencies and record info of those modules that wait
+    for (size_t i = 0; i < buildQueueItems.size(); i++)
+    {
+        BuildQueueItem& item = buildQueueItems[i];

        for (const ModuleName& dep : item.sourceNode->requireSet)
        {
@ -550,45 +607,41 @@ std::vector<ModuleName> Frontend::checkQueuedModules(
                {
                    item.dirtyDependencies++;

-                    state->buildQueueItems[moduleNameToQueue[dep]].reverseDeps.push_back(i);
+                    buildQueueItems[moduleNameToQueue[dep]].reverseDeps.push_back(i);
                }
            }
        }
+
+        if (item.dirtyDependencies == 0)
+            sendItemTask(i);
    }

-    // In the first pass, check all modules with no pending dependencies
-    for (size_t i = 0; i < state->buildQueueItems.size(); i++)
-    {
-        if (state->buildQueueItems[i].dirtyDependencies == 0)
-            sendQueueItemTask(state, i);
-    }
-
-    // If not a single item was found, a cycle in the graph was hit
-    if (state->processing == 0)
-        sendQueueCycleItemTask(state);
+    // Not a single item was found, a cycle in the graph was hit
+    if (processing == 0)
+        sendCycleItemTask();

    std::vector<size_t> nextItems;
    std::optional<size_t> itemWithException;
    bool cancelled = false;

-    while (state->remaining != 0)
+    while (remaining != 0)
    {
        {
-            std::unique_lock guard(state->mtx);
+            std::unique_lock guard(mtx);

            // If nothing is ready yet, wait
-            state->cv.wait(
+            cv.wait(
                guard,
-                [state]
+                [&readyQueueItems]
                {
-                    return !state->readyQueueItems.empty();
+                    return !readyQueueItems.empty();
                }
            );

            // Handle checked items
-            for (size_t i : state->readyQueueItems)
+            for (size_t i : readyQueueItems)
            {
-                const BuildQueueItem& item = state->buildQueueItems[i];
+                const BuildQueueItem& item = buildQueueItems[i];

                // If exception was thrown, stop adding new items and wait for processing items to complete
                if (item.exception)
@ -605,7 +658,7 @@ std::vector<ModuleName> Frontend::checkQueuedModules(
                // Notify items that were waiting for this dependency
                for (size_t reverseDep : item.reverseDeps)
                {
-                    BuildQueueItem& reverseDepItem = state->buildQueueItems[reverseDep];
+                    BuildQueueItem& reverseDepItem = buildQueueItems[reverseDep];

                    LUAU_ASSERT(reverseDepItem.dirtyDependencies != 0);
                    reverseDepItem.dirtyDependencies--;
@ -616,26 +669,26 @@ std::vector<ModuleName> Frontend::checkQueuedModules(
                }
            }

-            LUAU_ASSERT(state->processing >= state->readyQueueItems.size());
-            state->processing -= state->readyQueueItems.size();
+            LUAU_ASSERT(processing >= readyQueueItems.size());
+            processing -= readyQueueItems.size();

-            LUAU_ASSERT(state->remaining >= state->readyQueueItems.size());
-            state->remaining -= state->readyQueueItems.size();
-            state->readyQueueItems.clear();
+            LUAU_ASSERT(remaining >= readyQueueItems.size());
+            remaining -= readyQueueItems.size();
+            readyQueueItems.clear();
        }

        if (progress)
        {
-            if (!progress(state->buildQueueItems.size() - state->remaining, state->buildQueueItems.size()))
+            if (!progress(buildQueueItems.size() - remaining, buildQueueItems.size()))
                cancelled = true;
        }

        // Items cannot be submitted while holding the lock
        for (size_t i : nextItems)
-            sendQueueItemTask(state, i);
+            sendItemTask(i);
        nextItems.clear();

-        if (state->processing == 0)
+        if (processing == 0)
        {
            // Typechecking might have been cancelled by user, don't return partial results
            if (cancelled)
@ -643,19 +696,19 @@ std::vector<ModuleName> Frontend::checkQueuedModules(

            // We might have stopped because of a pending exception
            if (itemWithException)
-                recordItemResult(state->buildQueueItems[*itemWithException]);
+                recordItemResult(buildQueueItems[*itemWithException]);
        }

        // If we aren't done, but don't have anything processing, we hit a cycle
-        if (state->remaining != 0 && state->processing == 0)
-            sendQueueCycleItemTask(state);
+        if (remaining != 0 && processing == 0)
+            sendCycleItemTask();
    }

    std::vector<ModuleName> checkedModules;
-    checkedModules.reserve(state->buildQueueItems.size());
+    checkedModules.reserve(buildQueueItems.size());

-    for (size_t i = 0; i < state->buildQueueItems.size(); i++)
-        checkedModules.push_back(std::move(state->buildQueueItems[i].name));
+    for (size_t i = 0; i < buildQueueItems.size(); i++)
+        checkedModules.push_back(std::move(buildQueueItems[i].name));

    return checkedModules;
 }
@ -767,13 +820,6 @@ bool Frontend::parseGraph(
            topseen = Permanent;

            buildQueue.push_back(top->name);
-
-            // at this point we know all valid dependencies are processed into SourceNodes
-            for (const ModuleName& dep : top->requireSet)
-            {
-                if (auto it = sourceNodes.find(dep); it != sourceNodes.end())
-                    it->second->dependents.insert(top->name);
-            }
        }
        else
        {
@ -951,7 +997,7 @@ void Frontend::checkBuildQueueItem(BuildQueueItem& item)
        item.stats.timeCheck += duration;
        item.stats.filesStrict += 1;

-        if (item.options.customModuleCheck)
+        if (DFFlag::LuauRunCustomModuleChecks && item.options.customModuleCheck)
            item.options.customModuleCheck(sourceModule, *moduleForAutocomplete);

        item.module = moduleForAutocomplete;
@ -971,7 +1017,7 @@ void Frontend::checkBuildQueueItem(BuildQueueItem& item)
    item.stats.filesStrict += mode == Mode::Strict;
    item.stats.filesNonstrict += mode == Mode::Nonstrict;

-    if (item.options.customModuleCheck)
+    if (DFFlag::LuauRunCustomModuleChecks && item.options.customModuleCheck)
        item.options.customModuleCheck(sourceModule, *module);

    if (FFlag::LuauSolverV2 && mode == Mode::NoCheck)
@ -1003,8 +1049,6 @@ void Frontend::checkBuildQueueItem(BuildQueueItem& item)
        freeze(module->interfaceTypes);

        module->internalTypes.clear();
-        module->defArena.allocator.clear();
-        module->keyArena.allocator.clear();

        module->astTypes.clear();
        module->astTypePacks.clear();
@ -1058,35 +1102,17 @@ void Frontend::recordItemResult(const BuildQueueItem& item)
    if (item.exception)
        std::rethrow_exception(item.exception);

-    bool replacedModule = false;
    if (item.options.forAutocomplete)
    {
-        replacedModule = moduleResolverForAutocomplete.setModule(item.name, item.module);
+        moduleResolverForAutocomplete.setModule(item.name, item.module);
        item.sourceNode->dirtyModuleForAutocomplete = false;
    }
    else
    {
-        replacedModule = moduleResolver.setModule(item.name, item.module);
+        moduleResolver.setModule(item.name, item.module);
        item.sourceNode->dirtyModule = false;
    }

-    if (replacedModule)
-    {
-        LUAU_TIMETRACE_SCOPE("Frontend::invalidateDependentModules", "Frontend");
-        LUAU_TIMETRACE_ARGUMENT("name", item.name.c_str());
-        traverseDependents(
-            item.name,
-            [forAutocomplete = item.options.forAutocomplete](SourceNode& sourceNode)
-            {
-                bool traverseSubtree = !sourceNode.hasInvalidModuleDependency(forAutocomplete);
-                sourceNode.setInvalidModuleDependency(true, forAutocomplete);
-                return traverseSubtree;
-            }
-        );
-    }
-
-    item.sourceNode->setInvalidModuleDependency(false, item.options.forAutocomplete);
-
    stats.timeCheck += item.stats.timeCheck;
    stats.timeLint += item.stats.timeLint;

@ -1094,72 +1120,6 @@ void Frontend::recordItemResult(const BuildQueueItem& item)
    stats.filesNonstrict += item.stats.filesNonstrict;
 }

-void Frontend::performQueueItemTask(std::shared_ptr<BuildQueueWorkState> state, size_t itemPos)
-{
-    BuildQueueItem& item = state->buildQueueItems[itemPos];
-
-    if (DFFlag::LuauRethrowKnownExceptions)
-    {
-        try
-        {
-            checkBuildQueueItem(item);
-        }
-        catch (const Luau::InternalCompilerError&)
-        {
-            item.exception = std::current_exception();
-        }
-    }
-    else
-    {
-        try
-        {
-            checkBuildQueueItem(item);
-        }
-        catch (...)
-        {
-            item.exception = std::current_exception();
-        }
-    }
-
-    {
-        std::unique_lock guard(state->mtx);
-        state->readyQueueItems.push_back(itemPos);
-    }
-
-    state->cv.notify_one();
-}
-
-void Frontend::sendQueueItemTask(std::shared_ptr<BuildQueueWorkState> state, size_t itemPos)
-{
-    BuildQueueItem& item = state->buildQueueItems[itemPos];
-
-    LUAU_ASSERT(!item.processing);
-    item.processing = true;
-
-    state->processing++;
-
-    state->executeTask(
-        [this, state, itemPos]()
-        {
-            performQueueItemTask(state, itemPos);
-        }
-    );
-}
-
-void Frontend::sendQueueCycleItemTask(std::shared_ptr<BuildQueueWorkState> state)
-{
-    for (size_t i = 0; i < state->buildQueueItems.size(); i++)
-    {
-        BuildQueueItem& item = state->buildQueueItems[i];
-
-        if (!item.processing)
-        {
-            sendQueueItemTask(state, i);
-            break;
-        }
-    }
-}
-
 ScopePtr Frontend::getModuleEnvironment(const SourceModule& module, const Config& config, bool forAutocomplete) const
 {
    ScopePtr result;
@ -1187,12 +1147,6 @@ ScopePtr Frontend::getModuleEnvironment(const SourceModule& module, const Config
    return result;
 }

-bool Frontend::allModuleDependenciesValid(const ModuleName& name, bool forAutocomplete) const
-{
-    auto it = sourceNodes.find(name);
-    return it != sourceNodes.end() && !it->second->hasInvalidModuleDependency(forAutocomplete);
-}
-
 bool Frontend::isDirty(const ModuleName& name, bool forAutocomplete) const
 {
    auto it = sourceNodes.find(name);
@ -1207,35 +1161,16 @@ bool Frontend::isDirty(const ModuleName& name, bool forAutocomplete) const
 */
 void Frontend::markDirty(const ModuleName& name, std::vector<ModuleName>* markedDirty)
 {
-    LUAU_TIMETRACE_SCOPE("Frontend::markDirty", "Frontend");
-    LUAU_TIMETRACE_ARGUMENT("name", name.c_str());
-
-    traverseDependents(
-        name,
-        [markedDirty](SourceNode& sourceNode)
-        {
-            if (markedDirty)
-                markedDirty->push_back(sourceNode.name);
-
-            if (sourceNode.dirtySourceModule && sourceNode.dirtyModule && sourceNode.dirtyModuleForAutocomplete)
-                return false;
-
-            sourceNode.dirtySourceModule = true;
-            sourceNode.dirtyModule = true;
-            sourceNode.dirtyModuleForAutocomplete = true;
-
-            return true;
-        }
-    );
-}
-
-void Frontend::traverseDependents(const ModuleName& name, std::function<bool(SourceNode&)> processSubtree)
-{
-    LUAU_TIMETRACE_SCOPE("Frontend::traverseDependents", "Frontend");
-
    if (sourceNodes.count(name) == 0)
        return;

+    std::unordered_map<ModuleName, std::vector<ModuleName>> reverseDeps;
+    for (const auto& module : sourceNodes)
+    {
+        for (const auto& dep : module.second->requireSet)
+            reverseDeps[dep].push_back(module.first);
+    }
+
    std::vector<ModuleName> queue{name};

    while (!queue.empty())
@ -1246,10 +1181,22 @@ void Frontend::traverseDependents(const ModuleName& name, std::function<bool(Sou
        LUAU_ASSERT(sourceNodes.count(next) > 0);
        SourceNode& sourceNode = *sourceNodes[next];

-        if (!processSubtree(sourceNode))
+        if (markedDirty)
+            markedDirty->push_back(next);
+
+        if (sourceNode.dirtySourceModule && sourceNode.dirtyModule && sourceNode.dirtyModuleForAutocomplete)
            continue;

-        const Set<ModuleName>& dependents = sourceNode.dependents;
+        sourceNode.dirtySourceModule = true;
+        sourceNode.dirtyModule = true;
+        sourceNode.dirtyModuleForAutocomplete = true;
+
+        if (0 == reverseDeps.count(next))
+            continue;
+
+        sourceModules.erase(next);
+
+        const std::vector<ModuleName>& dependents = reverseDeps[next];
        queue.insert(queue.end(), dependents.begin(), dependents.end());
    }
 }
@ -1277,7 +1224,6 @@ ModulePtr check(
    NotNull<ModuleResolver> moduleResolver,
    NotNull<FileResolver> fileResolver,
    const ScopePtr& parentScope,
-    const ScopePtr& typeFunctionScope,
    std::function<void(const ModuleName&, const ScopePtr&)> prepareModuleScope,
    FrontendOptions options,
    TypeCheckLimits limits,
@ -1294,7 +1240,6 @@ ModulePtr check(
        moduleResolver,
        fileResolver,
        parentScope,
-        typeFunctionScope,
        std::move(prepareModuleScope),
        options,
        limits,
@ -1305,7 +1250,7 @@ ModulePtr check(

 struct InternalTypeFinder : TypeOnceVisitor
 {
-    bool visit(TypeId, const ExternType&) override
+    bool visit(TypeId, const ClassType&) override
    {
        return false;
    }
@ -1356,7 +1301,6 @@ ModulePtr check(
    NotNull<ModuleResolver> moduleResolver,
    NotNull<FileResolver> fileResolver,
    const ScopePtr& parentScope,
-    const ScopePtr& typeFunctionScope,
    std::function<void(const ModuleName&, const ScopePtr&)> prepareModuleScope,
    FrontendOptions options,
    TypeCheckLimits limits,
@ -1369,15 +1313,18 @@ ModulePtr check(
    LUAU_TIMETRACE_ARGUMENT("name", sourceModule.humanReadableName.c_str());

    ModulePtr result = std::make_shared<Module>();
-    result->checkedInNewSolver = true;
+    if (FFlag::LuauStoreSolverTypeOnModule)
+        result->checkedInNewSolver = true;
    result->name = sourceModule.name;
    result->humanReadableName = sourceModule.humanReadableName;
    result->mode = mode;
    result->internalTypes.owningModule = result.get();
    result->interfaceTypes.owningModule = result.get();
-    result->allocator = sourceModule.allocator;
-    result->names = sourceModule.names;
-    result->root = sourceModule.root;
+    if (FFlag::LuauReferenceAllocatorInNewSolver)
+    {
+        result->allocator = sourceModule.allocator;
+        result->names = sourceModule.names;
+    }

    iceHandler->moduleName = sourceModule.name;

@ -1402,7 +1349,7 @@ ModulePtr check(
    SimplifierPtr simplifier = newSimplifier(NotNull{&result->internalTypes}, builtinTypes);
    TypeFunctionRuntime typeFunctionRuntime{iceHandler, NotNull{&limits}};

-    typeFunctionRuntime.allowEvaluation = FFlag::LuauTypeFunResultInAutocomplete || sourceModule.parseErrors.empty();
+    typeFunctionRuntime.allowEvaluation = sourceModule.parseErrors.empty();

    ConstraintGenerator cg{
        result,
@ -1413,66 +1360,35 @@ ModulePtr check(
        builtinTypes,
        iceHandler,
        parentScope,
-        typeFunctionScope,
        std::move(prepareModuleScope),
        logger.get(),
        NotNull{&dfg},
        requireCycles
    };

-    // FIXME: Delete this flag when clipping FFlag::DebugLuauGreedyGeneralization.
-    //
-    // This optional<> only exists so that we can run one constructor when the flag
-    // is set, and another when it is unset.
-    std::optional<ConstraintSolver> cs;
+    cg.visitModuleRoot(sourceModule.root);
+    result->errors = std::move(cg.errors);

-    if (FFlag::DebugLuauGreedyGeneralization)
-    {
-        ConstraintSet constraintSet = cg.run(sourceModule.root);
-        result->errors = std::move(constraintSet.errors);
-
-        cs.emplace(
-            NotNull{&normalizer},
-            NotNull{simplifier.get()},
-            NotNull{&typeFunctionRuntime},
-            result->name,
-            moduleResolver,
-            requireCycles,
-            logger.get(),
-            NotNull{&dfg},
-            limits,
-            std::move(constraintSet)
-        );
-    }
-    else
-    {
-        cg.visitModuleRoot(sourceModule.root);
-        result->errors = std::move(cg.errors);
-
-        cs.emplace(
-            NotNull{&normalizer},
-            NotNull{simplifier.get()},
-            NotNull{&typeFunctionRuntime},
-            NotNull(cg.rootScope),
-            borrowConstraints(cg.constraints),
-            NotNull{&cg.scopeToFunction},
-            result->name,
-            moduleResolver,
-            requireCycles,
-            logger.get(),
-            NotNull{&dfg},
-            limits
-        );
-    }
-
-    LUAU_ASSERT(bool(cs));
+    ConstraintSolver cs{
+        NotNull{&normalizer},
+        NotNull{simplifier.get()},
+        NotNull{&typeFunctionRuntime},
+        NotNull(cg.rootScope),
+        borrowConstraints(cg.constraints),
+        result->name,
+        moduleResolver,
+        requireCycles,
+        logger.get(),
+        NotNull{&dfg},
+        limits
+    };

    if (options.randomizeConstraintResolutionSeed)
-        cs->randomize(*options.randomizeConstraintResolutionSeed);
+        cs.randomize(*options.randomizeConstraintResolutionSeed);

    try
    {
-        cs->run();
+        cs.run();
    }
    catch (const TimeLimitError&)
    {
@ -1492,12 +1408,12 @@ ModulePtr check(
            printf("%s\n", output.c_str());
    }

-    for (TypeError& e : cs->errors)
+    for (TypeError& e : cs.errors)
        result->errors.emplace_back(std::move(e));

    result->scopes = std::move(cg.scopes);
    result->type = sourceModule.type;
-    result->upperBoundContributors = std::move(cs->upperBoundContributors);
+    result->upperBoundContributors = std::move(cs.upperBoundContributors);

    if (result->timeout || result->cancelled)
    {
@ -1625,7 +1541,6 @@ ModulePtr Frontend::check(
                NotNull{forAutocomplete ? &moduleResolverForAutocomplete : &moduleResolver},
                NotNull{fileResolver},
                environmentScope ? *environmentScope : globals.globalScope,
-                globals.globalTypeFunctionScope,
                prepareModuleScopeWrap,
                options,
                typeCheckLimits,
@ -1723,14 +1638,6 @@ std::pair<SourceNode*, SourceModule*> Frontend::getSourceNode(const ModuleName&

    sourceNode->name = sourceModule->name;
    sourceNode->humanReadableName = sourceModule->humanReadableName;
-
-    // clear all prior dependents. we will re-add them after parsing the rest of the graph
-    for (const auto& [moduleName, _] : sourceNode->requireLocations)
-    {
-        if (auto depIt = sourceNodes.find(moduleName); depIt != sourceNodes.end())
-            depIt->second->dependents.erase(sourceNode->name);
-    }
-
    sourceNode->requireSet.clear();
    sourceNode->requireLocations.clear();
    sourceNode->dirtySourceModule = false;
@ -1852,13 +1759,11 @@ std::string FrontendModuleResolver::getHumanReadableModuleName(const ModuleName&
    return frontend->fileResolver->getHumanReadableModuleName(moduleName);
 }

-bool FrontendModuleResolver::setModule(const ModuleName& moduleName, ModulePtr module)
+void FrontendModuleResolver::setModule(const ModuleName& moduleName, ModulePtr module)
 {
    std::scoped_lock lock(moduleMutex);

-    bool replaced = modules.count(moduleName) > 0;
    modules[moduleName] = std::move(module);
-    return replaced;
 }

 void FrontendModuleResolver::clearModules()
--- a/Analysis/src/Generalization.cpp
+++ b/Analysis/src/Generalization.cpp
--- a/Analysis/src/GlobalTypes.cpp
+++ b/Analysis/src/GlobalTypes.cpp
@ -9,7 +9,6 @@ GlobalTypes::GlobalTypes(NotNull<BuiltinTypes> builtinTypes)
    : builtinTypes(builtinTypes)
 {
    globalScope = std::make_shared<Scope>(globalTypes.addTypePack(TypePackVar{FreeTypePack{TypeLevel{}}}));
-    globalTypeFunctionScope = std::make_shared<Scope>(globalTypes.addTypePack(TypePackVar{FreeTypePack{TypeLevel{}}}));

    globalScope->addBuiltinTypeBinding("any", TypeFun{{}, builtinTypes->anyType});
    globalScope->addBuiltinTypeBinding("nil", TypeFun{{}, builtinTypes->nilType});
--- a/Analysis/src/InferPolarity.cpp
+++ b/Analysis/src/InferPolarity.cpp
@ -1,169 +0,0 @@
-// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
-
-#include "Luau/DenseHash.h"
-#include "Luau/Polarity.h"
-#include "Luau/Scope.h"
-#include "Luau/VisitType.h"
-
-LUAU_FASTFLAG(LuauNonReentrantGeneralization2)
-
-namespace Luau
-{
-
-struct InferPolarity : TypeVisitor
-{
-    NotNull<TypeArena> arena;
-    NotNull<Scope> scope;
-
-    DenseHashMap<TypeId, Polarity> types{nullptr};
-    DenseHashMap<TypePackId, Polarity> packs{nullptr};
-
-    Polarity polarity = Polarity::Positive;
-
-    explicit InferPolarity(NotNull<TypeArena> arena, NotNull<Scope> scope)
-        : arena(arena)
-        , scope(scope)
-    {
-    }
-
-    void flip()
-    {
-        polarity = invert(polarity);
-    }
-
-    bool visit(TypeId ty, const GenericType& gt) override
-    {
-        if (ty->owningArena != arena)
-            return false;
-
-        if (subsumes(scope, gt.scope))
-            types[ty] |= polarity;
-
-        return false;
-    }
-
-    bool visit(TypeId ty, const TableType& tt) override
-    {
-        if (ty->owningArena != arena)
-            return false;
-
-        const Polarity p = polarity;
-        for (const auto& [name, prop] : tt.props)
-        {
-            if (prop.isShared())
-            {
-                polarity = Polarity::Mixed;
-                traverse(prop.type());
-            }
-            else if (prop.isReadOnly())
-            {
-                polarity = p;
-                traverse(*prop.readTy);
-            }
-            else if (prop.isWriteOnly())
-            {
-                polarity = invert(p);
-                traverse(*prop.writeTy);
-            }
-            else
-                LUAU_ASSERT(!"Unreachable");
-        }
-
-        if (tt.indexer)
-        {
-            polarity = Polarity::Mixed;
-            traverse(tt.indexer->indexType);
-            traverse(tt.indexer->indexResultType);
-        }
-
-        polarity = p;
-
-        return false;
-    }
-
-    bool visit(TypeId ty, const FunctionType& ft) override
-    {
-        if (ty->owningArena != arena)
-            return false;
-
-        const Polarity p = polarity;
-
-        polarity = Polarity::Positive;
-
-        // If these types actually occur within the function signature, their
-        // polarity will be overwritten. If not, we infer that they are phantom
-        // types.
-        for (TypeId generic : ft.generics)
-        {
-            generic = follow(generic);
-            const auto gen = get<GenericType>(generic);
-            if (gen && subsumes(scope, gen->scope))
-                types[generic] = Polarity::None;
-        }
-        for (TypePackId genericPack : ft.genericPacks)
-        {
-            genericPack = follow(genericPack);
-            const auto gen = get<GenericTypePack>(genericPack);
-            if (gen && subsumes(scope, gen->scope))
-                packs[genericPack] = Polarity::None;
-        }
-
-        flip();
-        traverse(ft.argTypes);
-        flip();
-        traverse(ft.retTypes);
-
-        polarity = p;
-
-        return false;
-    }
-
-    bool visit(TypeId, const ExternType&) override
-    {
-        return false;
-    }
-
-    bool visit(TypePackId tp, const GenericTypePack& gtp) override
-    {
-        packs[tp] |= polarity;
-        return false;
-    }
-};
-
-template<typename TID>
-static void inferGenericPolarities_(NotNull<TypeArena> arena, NotNull<Scope> scope, TID ty)
-{
-    if (!FFlag::LuauNonReentrantGeneralization2)
-        return;
-
-    InferPolarity infer{arena, scope};
-    infer.traverse(ty);
-
-    for (const auto& [ty, polarity] : infer.types)
-    {
-        auto gt = getMutable<GenericType>(ty);
-        LUAU_ASSERT(gt);
-        gt->polarity = polarity;
-    }
-
-    for (const auto& [tp, polarity] : infer.packs)
-    {
-        if (tp->owningArena != arena)
-            continue;
-        auto gp = getMutable<GenericTypePack>(tp);
-        LUAU_ASSERT(gp);
-        gp->polarity = polarity;
-    }
-}
-
-void inferGenericPolarities(NotNull<TypeArena> arena, NotNull<Scope> scope, TypeId ty)
-{
-    inferGenericPolarities_(arena, scope, ty);
-}
-
-void inferGenericPolarities(NotNull<TypeArena> arena, NotNull<Scope> scope, TypePackId tp)
-{
-    inferGenericPolarities_(arena, scope, tp);
-}
-
-} // namespace Luau
--- a/Analysis/src/Instantiation.cpp
+++ b/Analysis/src/Instantiation.cpp
@ -49,7 +49,7 @@ bool Instantiation::ignoreChildren(TypeId ty)
 {
    if (log->getMutable<FunctionType>(ty))
        return true;
-    else if (get<ExternType>(ty))
+    else if (get<ClassType>(ty))
        return true;
    else
        return false;
@ -60,7 +60,7 @@ TypeId Instantiation::clean(TypeId ty)
    const FunctionType* ftv = log->getMutable<FunctionType>(ty);
    LUAU_ASSERT(ftv);

-    FunctionType clone = FunctionType{level, ftv->argTypes, ftv->retTypes, ftv->definition, ftv->hasSelf};
+    FunctionType clone = FunctionType{level, scope, ftv->argTypes, ftv->retTypes, ftv->definition, ftv->hasSelf};
    clone.magic = ftv->magic;
    clone.tags = ftv->tags;
    clone.argNames = ftv->argNames;
@ -119,7 +119,7 @@ bool ReplaceGenerics::ignoreChildren(TypeId ty)
        // whenever we quantify, so the vectors overlap if and only if they are equal.
        return (!generics.empty() || !genericPacks.empty()) && (ftv->generics == generics) && (ftv->genericPacks == genericPacks);
    }
-    else if (get<ExternType>(ty))
+    else if (get<ClassType>(ty))
        return true;
    else
    {
@ -163,7 +163,7 @@ TypeId ReplaceGenerics::clean(TypeId ty)
    }
    else
    {
-        return arena->freshType(builtinTypes, scope, level);
+        return addType(FreeType{scope, level});
    }
 }

--- a/Analysis/src/Instantiation2.cpp
+++ b/Analysis/src/Instantiation2.cpp
@ -6,7 +6,7 @@ namespace Luau

 bool Instantiation2::ignoreChildren(TypeId ty)
 {
-    if (get<ExternType>(ty))
+    if (get<ClassType>(ty))
        return true;

    if (auto ftv = get<FunctionType>(ty))
--- a/Analysis/src/IostreamHelpers.cpp
+++ b/Analysis/src/IostreamHelpers.cpp
@ -193,8 +193,8 @@ static void errorToString(std::ostream& stream, const T& err)
        stream << "NormalizationTooComplex { }";
    else if constexpr (std::is_same_v<T, TypePackMismatch>)
        stream << "TypePackMismatch { wanted = '" + toString(err.wantedTp) + "', given = '" + toString(err.givenTp) + "' }";
-    else if constexpr (std::is_same_v<T, DynamicPropertyLookupOnExternTypesUnsafe>)
-        stream << "DynamicPropertyLookupOnExternTypesUnsafe { " << toString(err.ty) << " }";
+    else if constexpr (std::is_same_v<T, DynamicPropertyLookupOnClassesUnsafe>)
+        stream << "DynamicPropertyLookupOnClassesUnsafe { " << toString(err.ty) << " }";
    else if constexpr (std::is_same_v<T, UninhabitedTypeFunction>)
        stream << "UninhabitedTypeFunction { " << toString(err.ty) << " }";
    else if constexpr (std::is_same_v<T, ExplicitFunctionAnnotationRecommended>)
@ -229,8 +229,6 @@ static void errorToString(std::ostream& stream, const T& err)
        stream << "UnexpectedTypePackInSubtyping {  tp = '" + toString(err.tp) + "' }";
    else if constexpr (std::is_same_v<T, UserDefinedTypeFunctionError>)
        stream << "UserDefinedTypeFunctionError { " << err.message << " }";
-    else if constexpr (std::is_same_v<T, ReservedIdentifier>)
-        stream << "ReservedIdentifier { " << err.name << " }";
    else if constexpr (std::is_same_v<T, CannotAssignToNever>)
    {
        stream << "CannotAssignToNever { rvalueType = '" << toString(err.rhsType) << "', reason = '" << err.reason << "', cause = { ";
--- a/Analysis/src/Linter.cpp
+++ b/Analysis/src/Linter.cpp
@ -19,9 +19,6 @@ LUAU_FASTFLAG(LuauSolverV2)
 LUAU_FASTFLAG(LuauAttribute)
 LUAU_FASTFLAGVARIABLE(LintRedundantNativeAttribute)

-LUAU_FASTFLAG(LuauDeprecatedAttribute)
-LUAU_FASTFLAG(LuauStoreReturnTypesAsPackOnAst)
-
 namespace Luau
 {

@ -909,11 +906,6 @@ private:
        return true;
    }

-    bool visit(AstTypePack* node) override
-    {
-        return FFlag::LuauStoreReturnTypesAsPackOnAst;
-    }
-
    bool visit(AstTypeReference* node) override
    {
        if (!node->prefix)
@ -1976,11 +1968,6 @@ private:
        return true;
    }

-    bool visit(AstTypePack* node) override
-    {
-        return FFlag::LuauStoreReturnTypesAsPackOnAst;
-    }
-
    bool visit(AstTypeTable* node) override
    {
        if (FFlag::LuauSolverV2)
@ -2293,57 +2280,6 @@ private:
    {
    }

-    bool visit(AstExprLocal* node) override
-    {
-        if (FFlag::LuauDeprecatedAttribute)
-        {
-
-            const FunctionType* fty = getFunctionType(node);
-            bool shouldReport = fty && fty->isDeprecatedFunction && !inScope(fty);
-
-            if (shouldReport)
-                report(node->location, node->local->name.value);
-        }
-
-        return true;
-    }
-
-    bool visit(AstExprGlobal* node) override
-    {
-        if (FFlag::LuauDeprecatedAttribute)
-        {
-            const FunctionType* fty = getFunctionType(node);
-            bool shouldReport = fty && fty->isDeprecatedFunction && !inScope(fty);
-
-            if (shouldReport)
-                report(node->location, node->name.value);
-        }
-
-        return true;
-    }
-
-    bool visit(AstStatLocalFunction* node) override
-    {
-        if (FFlag::LuauDeprecatedAttribute)
-        {
-            check(node->func);
-            return false;
-        }
-        else
-            return true;
-    }
-
-    bool visit(AstStatFunction* node) override
-    {
-        if (FFlag::LuauDeprecatedAttribute)
-        {
-            check(node->func);
-            return false;
-        }
-        else
-            return true;
-    }
-
    bool visit(AstExprIndexName* node) override
    {
        if (std::optional<TypeId> ty = context->getType(node->expr))
@ -2383,65 +2319,24 @@ private:

    void check(AstExprIndexName* node, TypeId ty)
    {
-        if (const ExternType* cty = get<ExternType>(ty))
+        if (const ClassType* cty = get<ClassType>(ty))
        {
-            const Property* prop = lookupExternTypeProp(cty, node->index.value);
+            const Property* prop = lookupClassProp(cty, node->index.value);

            if (prop && prop->deprecated)
                report(node->location, *prop, cty->name.c_str(), node->index.value);
-            else if (FFlag::LuauDeprecatedAttribute && prop)
-            {
-                if (std::optional<TypeId> ty = prop->readTy)
-                {
-                    const FunctionType* fty = get<FunctionType>(follow(ty));
-                    bool shouldReport = fty && fty->isDeprecatedFunction && !inScope(fty);
-
-                    if (shouldReport)
-                    {
-                        const char* className = nullptr;
-                        if (AstExprGlobal* global = node->expr->as<AstExprGlobal>())
-                            className = global->name.value;
-
-                        const char* functionName = node->index.value;
-
-                        report(node->location, className, functionName);
-                    }
-                }
-            }
        }
        else if (const TableType* tty = get<TableType>(ty))
        {
            auto prop = tty->props.find(node->index.value);

-            if (prop != tty->props.end())
+            if (prop != tty->props.end() && prop->second.deprecated)
            {
-                if (prop->second.deprecated)
-                {
-                    // strip synthetic typeof() for builtin tables
-                    if (tty->name && tty->name->compare(0, 7, "typeof(") == 0 && tty->name->back() == ')')
-                        report(node->location, prop->second, tty->name->substr(7, tty->name->length() - 8).c_str(), node->index.value);
-                    else
-                        report(node->location, prop->second, tty->name ? tty->name->c_str() : nullptr, node->index.value);
-                }
-                else if (FFlag::LuauDeprecatedAttribute)
-                {
-                    if (std::optional<TypeId> ty = prop->second.readTy)
-                    {
-                        const FunctionType* fty = get<FunctionType>(follow(ty));
-                        bool shouldReport = fty && fty->isDeprecatedFunction && !inScope(fty);
-
-                        if (shouldReport)
-                        {
-                            const char* className = nullptr;
-                            if (AstExprGlobal* global = node->expr->as<AstExprGlobal>())
-                                className = global->name.value;
-
-                            const char* functionName = node->index.value;
-
-                            report(node->location, className, functionName);
-                        }
-                    }
-                }
+                // strip synthetic typeof() for builtin tables
+                if (tty->name && tty->name->compare(0, 7, "typeof(") == 0 && tty->name->back() == ')')
+                    report(node->location, prop->second, tty->name->substr(7, tty->name->length() - 8).c_str(), node->index.value);
+                else
+                    report(node->location, prop->second, tty->name ? tty->name->c_str() : nullptr, node->index.value);
            }
        }
    }
@ -2460,26 +2355,6 @@ private:
        }
    }

-    void check(AstExprFunction* func)
-    {
-        LUAU_ASSERT(FFlag::LuauDeprecatedAttribute);
-        LUAU_ASSERT(func);
-
-        const FunctionType* fty = getFunctionType(func);
-        bool isDeprecated = fty && fty->isDeprecatedFunction;
-
-        // If a function is deprecated, we don't want to flag its recursive uses.
-        // So we push it on a stack while its body is being analyzed.
-        // When a deprecated function is used, we check the stack to ensure that we are not inside that function.
-        if (isDeprecated)
-            pushScope(fty);
-
-        func->visit(this);
-
-        if (isDeprecated)
-            popScope(fty);
-    }
-
    void report(const Location& location, const Property& prop, const char* container, const char* field)
    {
        std::string suggestion = prop.deprecatedSuggestion.empty() ? "" : format(", use '%s' instead", prop.deprecatedSuggestion.c_str());
@ -2489,63 +2364,6 @@ private:
        else
            emitWarning(*context, LintWarning::Code_DeprecatedApi, location, "Member '%s' is deprecated%s", field, suggestion.c_str());
    }
-
-    void report(const Location& location, const char* tableName, const char* functionName)
-    {
-        LUAU_ASSERT(FFlag::LuauDeprecatedAttribute);
-
-        if (tableName)
-            emitWarning(*context, LintWarning::Code_DeprecatedApi, location, "Member '%s.%s' is deprecated", tableName, functionName);
-        else
-            emitWarning(*context, LintWarning::Code_DeprecatedApi, location, "Member '%s' is deprecated", functionName);
-    }
-
-    void report(const Location& location, const char* functionName)
-    {
-        LUAU_ASSERT(FFlag::LuauDeprecatedAttribute);
-
-        emitWarning(*context, LintWarning::Code_DeprecatedApi, location, "Function '%s' is deprecated", functionName);
-    }
-
-    std::vector<const FunctionType*> functionTypeScopeStack;
-
-    void pushScope(const FunctionType* fty)
-    {
-        LUAU_ASSERT(FFlag::LuauDeprecatedAttribute);
-        LUAU_ASSERT(fty);
-
-        functionTypeScopeStack.push_back(fty);
-    }
-
-    void popScope(const FunctionType* fty)
-    {
-        LUAU_ASSERT(FFlag::LuauDeprecatedAttribute);
-        LUAU_ASSERT(fty);
-
-        LUAU_ASSERT(fty == functionTypeScopeStack.back());
-        functionTypeScopeStack.pop_back();
-    }
-
-    bool inScope(const FunctionType* fty) const
-    {
-        LUAU_ASSERT(FFlag::LuauDeprecatedAttribute);
-        LUAU_ASSERT(fty);
-
-        return std::find(functionTypeScopeStack.begin(), functionTypeScopeStack.end(), fty) != functionTypeScopeStack.end();
-    }
-
-    const FunctionType* getFunctionType(AstExpr* node)
-    {
-        LUAU_ASSERT(FFlag::LuauDeprecatedAttribute);
-
-        std::optional<TypeId> ty = context->getType(node);
-        if (!ty)
-            return nullptr;
-
-        const FunctionType* fty = get<FunctionType>(follow(ty));
-
-        return fty;
-    }
 };

 class LintTableOperations : AstVisitor
--- a/Analysis/src/Module.cpp
+++ b/Analysis/src/Module.cpp
@ -15,27 +15,22 @@
 #include <algorithm>

 LUAU_FASTFLAG(LuauSolverV2);
-LUAU_FASTFLAG(LuauRetainDefinitionAliasLocations)
+LUAU_FASTFLAGVARIABLE(LuauIncrementalAutocompleteCommentDetection)

 namespace Luau
 {

-static void defaultLogLuau(std::string_view context, std::string_view input)
+static bool contains_DEPRECATED(Position pos, Comment comment)
 {
-    // The default is to do nothing because we don't want to mess with
-    // the xml parsing done by the dcr script.
-}
-
-Luau::LogLuauProc logLuau = &defaultLogLuau;
-
-void setLogLuau(LogLuauProc ll)
-{
-    logLuau = ll;
-}
-
-void resetLogLuauProc()
-{
-    logLuau = &defaultLogLuau;
+    if (comment.location.contains(pos))
+        return true;
+    else if (comment.type == Lexeme::BrokenComment && comment.location.begin <= pos) // Broken comments are broken specifically because they don't
+                                                                                     // have an end
+        return true;
+    else if (comment.type == Lexeme::Comment && comment.location.end == pos)
+        return true;
+    else
+        return false;
 }

 static bool contains(Position pos, Comment comment)
@ -61,8 +56,11 @@ bool isWithinComment(const std::vector<Comment>& commentLocations, Position pos)
        Comment{Lexeme::Comment, Location{pos, pos}},
        [](const Comment& a, const Comment& b)
        {
-            if (a.type == Lexeme::Comment)
-                return a.location.end.line < b.location.end.line;
+            if (FFlag::LuauIncrementalAutocompleteCommentDetection)
+            {
+                if (a.type == Lexeme::Comment)
+                    return a.location.end.line < b.location.end.line;
+            }
            return a.location.end < b.location.end;
        }
    );
@ -70,7 +68,7 @@ bool isWithinComment(const std::vector<Comment>& commentLocations, Position pos)
    if (iter == commentLocations.end())
        return false;

-    if (contains(pos, *iter))
+    if (FFlag::LuauIncrementalAutocompleteCommentDetection ? contains(pos, *iter) : contains_DEPRECATED(pos, *iter))
        return true;

    // Due to the nature of std::lower_bound, it is possible that iter points at a comment that ends
@ -154,6 +152,8 @@ struct ClonePublicInterface : Substitution
            }

            ftv->level = TypeLevel{0, 0};
+            if (FFlag::LuauSolverV2)
+                ftv->scope = nullptr;
        }
        else if (TableType* ttv = getMutable<TableType>(result))
        {
@ -265,10 +265,7 @@ struct ClonePublicInterface : Substitution

        TypeId type = cloneType(tf.type);

-        if (FFlag::LuauRetainDefinitionAliasLocations)
-            return TypeFun{typeParams, typePackParams, type, tf.definitionLocation};
-        else
-            return TypeFun{typeParams, typePackParams, type};
+        return TypeFun{typeParams, typePackParams, type};
    }
 };

--- a/Analysis/src/NonStrictTypeChecker.cpp
+++ b/Analysis/src/NonStrictTypeChecker.cpp
@ -2,7 +2,6 @@
 #include "Luau/NonStrictTypeChecker.h"

 #include "Luau/Ast.h"
-#include "Luau/AstQuery.h"
 #include "Luau/Common.h"
 #include "Luau/Simplify.h"
 #include "Luau/Type.h"
@ -15,17 +14,12 @@
 #include "Luau/TypeFunction.h"
 #include "Luau/Def.h"
 #include "Luau/ToString.h"
-#include "Luau/TypeUtils.h"
+#include "Luau/TypeFwd.h"

 #include <iostream>
 #include <iterator>

-LUAU_FASTFLAG(DebugLuauMagicTypes)
-
-LUAU_FASTFLAGVARIABLE(LuauNonStrictVisitorImprovements)
-LUAU_FASTFLAGVARIABLE(LuauNewNonStrictWarnOnUnknownGlobals)
-LUAU_FASTFLAGVARIABLE(LuauNewNonStrictVisitTypes2)
-LUAU_FASTFLAG(LuauStoreReturnTypesAsPackOnAst)
+LUAU_FASTFLAGVARIABLE(LuauCountSelfCallsNonstrict)

 namespace Luau
 {
@ -217,7 +211,7 @@ struct NonStrictTypeChecker
            return *fst;
        else if (auto ftp = get<FreeTypePack>(pack))
        {
-            TypeId result = arena->freshType(builtinTypes, ftp->scope);
+            TypeId result = arena->addType(FreeType{ftp->scope});
            TypePackId freeTail = arena->addTypePack(FreeTypePack{ftp->scope});

            TypePack* resultPack = emplaceTypePack<TypePack>(asMutable(pack));
@ -311,7 +305,7 @@ struct NonStrictTypeChecker
            return visit(s);
        else if (auto s = stat->as<AstStatDeclareGlobal>())
            return visit(s);
-        else if (auto s = stat->as<AstStatDeclareExternType>())
+        else if (auto s = stat->as<AstStatDeclareClass>())
            return visit(s);
        else if (auto s = stat->as<AstStatError>())
            return visit(s);
@ -337,12 +331,7 @@ struct NonStrictTypeChecker
                // local x ; B generates the context of B without x
                visit(local);
                for (auto local : local->vars)
-                {
                    ctx.remove(dfg->getDef(local));
-
-                    if (FFlag::LuauNewNonStrictVisitTypes2)
-                        visit(local->annotation);
-                }
            }
            else
                ctx = NonStrictContext::disjunction(builtinTypes, arena, visit(stat), ctx);
@ -352,9 +341,8 @@ struct NonStrictTypeChecker

    NonStrictContext visit(AstStatIf* ifStatement)
    {
-        NonStrictContext condB = visit(ifStatement->condition, ValueContext::RValue);
+        NonStrictContext condB = visit(ifStatement->condition);
        NonStrictContext branchContext;
-
        // If there is no else branch, don't bother generating warnings for the then branch - we can't prove there is an error
        if (ifStatement->elsebody)
        {
@ -362,32 +350,17 @@ struct NonStrictTypeChecker
            NonStrictContext elseBody = visit(ifStatement->elsebody);
            branchContext = NonStrictContext::conjunction(builtinTypes, arena, thenBody, elseBody);
        }
-
        return NonStrictContext::disjunction(builtinTypes, arena, condB, branchContext);
    }

    NonStrictContext visit(AstStatWhile* whileStatement)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            NonStrictContext condition = visit(whileStatement->condition, ValueContext::RValue);
-            NonStrictContext body = visit(whileStatement->body);
-            return NonStrictContext::disjunction(builtinTypes, arena, condition, body);
-        }
-        else
-            return {};
+        return {};
    }

    NonStrictContext visit(AstStatRepeat* repeatStatement)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            NonStrictContext body = visit(repeatStatement->body);
-            NonStrictContext condition = visit(repeatStatement->condition, ValueContext::RValue);
-            return NonStrictContext::disjunction(builtinTypes, arena, body, condition);
-        }
-        else
-            return {};
+        return {};
    }

    NonStrictContext visit(AstStatBreak* breakStatement)
@ -402,113 +375,53 @@ struct NonStrictTypeChecker

    NonStrictContext visit(AstStatReturn* returnStatement)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            // TODO: this is believing existing code, but i'm not sure if this makes sense
-            // for how the contexts are handled
-            for (AstExpr* expr : returnStatement->list)
-                visit(expr, ValueContext::RValue);
-        }
-
        return {};
    }

    NonStrictContext visit(AstStatExpr* expr)
    {
-        return visit(expr->expr, ValueContext::RValue);
+        return visit(expr->expr);
    }

    NonStrictContext visit(AstStatLocal* local)
    {
        for (AstExpr* rhs : local->values)
-            visit(rhs, ValueContext::RValue);
+            visit(rhs);
        return {};
    }

    NonStrictContext visit(AstStatFor* forStatement)
    {
-        if (FFlag::LuauNewNonStrictVisitTypes2)
-            visit(forStatement->var->annotation);
-
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            // TODO: throwing out context based on same principle as existing code?
-            if (forStatement->from)
-                visit(forStatement->from, ValueContext::RValue);
-            if (forStatement->to)
-                visit(forStatement->to, ValueContext::RValue);
-            if (forStatement->step)
-                visit(forStatement->step, ValueContext::RValue);
-            return visit(forStatement->body);
-        }
-        else
-        {
-            return {};
-        }
+        return {};
    }

    NonStrictContext visit(AstStatForIn* forInStatement)
    {
-        if (FFlag::LuauNewNonStrictVisitTypes2)
-        {
-            for (auto var : forInStatement->vars)
-                visit(var->annotation);
-        }
-
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            for (AstExpr* rhs : forInStatement->values)
-                visit(rhs, ValueContext::RValue);
-            return visit(forInStatement->body);
-        }
-        else
-        {
-            return {};
-        }
+        return {};
    }

    NonStrictContext visit(AstStatAssign* assign)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            for (AstExpr* lhs : assign->vars)
-                visit(lhs, ValueContext::LValue);
-            for (AstExpr* rhs : assign->values)
-                visit(rhs, ValueContext::RValue);
-        }
-
        return {};
    }

    NonStrictContext visit(AstStatCompoundAssign* compoundAssign)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            visit(compoundAssign->var, ValueContext::LValue);
-            visit(compoundAssign->value, ValueContext::RValue);
-        }
-
        return {};
    }

    NonStrictContext visit(AstStatFunction* statFn)
    {
-        return visit(statFn->func, ValueContext::RValue);
+        return visit(statFn->func);
    }

    NonStrictContext visit(AstStatLocalFunction* localFn)
    {
-        return visit(localFn->func, ValueContext::RValue);
+        return visit(localFn->func);
    }

    NonStrictContext visit(AstStatTypeAlias* typeAlias)
    {
-        if (FFlag::LuauNewNonStrictVisitTypes2)
-        {
-            visitGenerics(typeAlias->generics, typeAlias->genericPacks);
-            visit(typeAlias->type);
-        }
-
        return {};
    }

@ -519,59 +432,29 @@ struct NonStrictTypeChecker

    NonStrictContext visit(AstStatDeclareFunction* declFn)
    {
-        if (FFlag::LuauNewNonStrictVisitTypes2)
-        {
-            visitGenerics(declFn->generics, declFn->genericPacks);
-            visit(declFn->params);
-            visit(declFn->retTypes);
-        }
-
        return {};
    }

    NonStrictContext visit(AstStatDeclareGlobal* declGlobal)
    {
-        if (FFlag::LuauNewNonStrictVisitTypes2)
-            visit(declGlobal->type);
-
        return {};
    }

-    NonStrictContext visit(AstStatDeclareExternType* declClass)
+    NonStrictContext visit(AstStatDeclareClass* declClass)
    {
-        if (FFlag::LuauNewNonStrictVisitTypes2)
-        {
-            if (declClass->indexer)
-            {
-                visit(declClass->indexer->indexType);
-                visit(declClass->indexer->resultType);
-            }
-
-            for (auto prop : declClass->props)
-                visit(prop.ty);
-        }
-
        return {};
    }

    NonStrictContext visit(AstStatError* error)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            for (AstStat* stat : error->statements)
-                visit(stat);
-            for (AstExpr* expr : error->expressions)
-                visit(expr, ValueContext::RValue);
-        }
-
        return {};
    }

-    NonStrictContext visit(AstExpr* expr, ValueContext context)
+    NonStrictContext visit(AstExpr* expr)
    {
        auto pusher = pushStack(expr);
        if (auto e = expr->as<AstExprGroup>())
-            return visit(e, context);
+            return visit(e);
        else if (auto e = expr->as<AstExprConstantNil>())
            return visit(e);
        else if (auto e = expr->as<AstExprConstantBool>())
@ -581,17 +464,17 @@ struct NonStrictTypeChecker
        else if (auto e = expr->as<AstExprConstantString>())
            return visit(e);
        else if (auto e = expr->as<AstExprLocal>())
-            return visit(e, context);
+            return visit(e);
        else if (auto e = expr->as<AstExprGlobal>())
-            return visit(e, context);
+            return visit(e);
        else if (auto e = expr->as<AstExprVarargs>())
            return visit(e);
        else if (auto e = expr->as<AstExprCall>())
            return visit(e);
        else if (auto e = expr->as<AstExprIndexName>())
-            return visit(e, context);
+            return visit(e);
        else if (auto e = expr->as<AstExprIndexExpr>())
-            return visit(e, context);
+            return visit(e);
        else if (auto e = expr->as<AstExprFunction>())
            return visit(e);
        else if (auto e = expr->as<AstExprTable>())
@ -615,12 +498,9 @@ struct NonStrictTypeChecker
        }
    }

-    NonStrictContext visit(AstExprGroup* group, ValueContext context)
+    NonStrictContext visit(AstExprGroup* group)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-            return visit(group->expr, context);
-        else
-            return {};
+        return {};
    }

    NonStrictContext visit(AstExprConstantNil* expr)
@ -643,36 +523,34 @@ struct NonStrictTypeChecker
        return {};
    }

-    NonStrictContext visit(AstExprLocal* local, ValueContext context)
+    NonStrictContext visit(AstExprLocal* local)
    {
        return {};
    }

-    NonStrictContext visit(AstExprGlobal* global, ValueContext context)
+    NonStrictContext visit(AstExprGlobal* global)
    {
-        if (FFlag::LuauNewNonStrictWarnOnUnknownGlobals)
-        {
-            // We don't file unknown symbols for LValues.
-            if (context == ValueContext::LValue)
-                return {};
-
-            NotNull<Scope> scope = stack.back();
-            if (!scope->lookup(global->name))
-            {
-                reportError(UnknownSymbol{global->name.value, UnknownSymbol::Binding}, global->location);
-            }
-        }
-
        return {};
    }

-    NonStrictContext visit(AstExprVarargs* varargs)
+    NonStrictContext visit(AstExprVarargs* global)
    {
        return {};
    }

    NonStrictContext visit(AstExprCall* call)
    {
+        if (FFlag::LuauCountSelfCallsNonstrict)
+            return visitCall(call);
+        else
+            return visitCall_DEPRECATED(call);
+    }
+
+    // rename this to `visit` when `FFlag::LuauCountSelfCallsNonstrict` is removed, and clean up above `visit`.
+    NonStrictContext visitCall(AstExprCall* call)
+    {
+        LUAU_ASSERT(FFlag::LuauCountSelfCallsNonstrict);
+
        NonStrictContext fresh{};
        TypeId* originalCallTy = module->astOriginalCallTypes.find(call->func);
        if (!originalCallTy)
@ -781,24 +659,117 @@ struct NonStrictTypeChecker
        return fresh;
    }

-    NonStrictContext visit(AstExprIndexName* indexName, ValueContext context)
+    // Remove with `FFlag::LuauCountSelfCallsNonstrict` clean up.
+    NonStrictContext visitCall_DEPRECATED(AstExprCall* call)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-            return visit(indexName->expr, context);
-        else
-            return {};
+        LUAU_ASSERT(!FFlag::LuauCountSelfCallsNonstrict);
+
+        NonStrictContext fresh{};
+        TypeId* originalCallTy = module->astOriginalCallTypes.find(call->func);
+        if (!originalCallTy)
+            return fresh;
+
+        TypeId fnTy = *originalCallTy;
+        if (auto fn = get<FunctionType>(follow(fnTy)))
+        {
+            if (fn->isCheckedFunction)
+            {
+                // We know fn is a checked function, which means it looks like:
+                // (S1, ... SN) -> T &
+                // (~S1, unknown^N-1) -> error &
+                // (unknown, ~S2, unknown^N-2) -> error
+                // ...
+                // ...
+                // (unknown^N-1, ~S_N) -> error
+                std::vector<TypeId> argTypes;
+                argTypes.reserve(call->args.size);
+                // Pad out the arg types array with the types you would expect to see
+                TypePackIterator curr = begin(fn->argTypes);
+                TypePackIterator fin = end(fn->argTypes);
+                while (curr != fin)
+                {
+                    argTypes.push_back(*curr);
+                    ++curr;
+                }
+                if (auto argTail = curr.tail())
+                {
+                    if (const VariadicTypePack* vtp = get<VariadicTypePack>(follow(*argTail)))
+                    {
+                        while (argTypes.size() < call->args.size)
+                        {
+                            argTypes.push_back(vtp->ty);
+                        }
+                    }
+                }
+
+                std::string functionName = getFunctionNameAsString(*call->func).value_or("");
+                if (call->args.size > argTypes.size())
+                {
+                    // We are passing more arguments than we expect, so we should error
+                    reportError(CheckedFunctionIncorrectArgs{functionName, argTypes.size(), call->args.size}, call->location);
+                    return fresh;
+                }
+
+                for (size_t i = 0; i < call->args.size; i++)
+                {
+                    // For example, if the arg is "hi"
+                    // The actual arg type is string
+                    // The expected arg type is number
+                    // The type of the argument in the overload is ~number
+                    // We will compare arg and ~number
+                    AstExpr* arg = call->args.data[i];
+                    TypeId expectedArgType = argTypes[i];
+                    std::shared_ptr<const NormalizedType> norm = normalizer.normalize(expectedArgType);
+                    DefId def = dfg->getDef(arg);
+                    TypeId runTimeErrorTy;
+                    // If we're dealing with any, negating any will cause all subtype tests to fail
+                    // However, when someone calls this function, they're going to want to be able to pass it anything,
+                    // for that reason, we manually inject never into the context so that the runtime test will always pass.
+                    if (!norm)
+                        reportError(NormalizationTooComplex{}, arg->location);
+
+                    if (norm && get<AnyType>(norm->tops))
+                        runTimeErrorTy = builtinTypes->neverType;
+                    else
+                        runTimeErrorTy = getOrCreateNegation(expectedArgType);
+                    fresh.addContext(def, runTimeErrorTy);
+                }
+
+                // Populate the context and now iterate through each of the arguments to the call to find out if we satisfy the types
+                for (size_t i = 0; i < call->args.size; i++)
+                {
+                    AstExpr* arg = call->args.data[i];
+                    if (auto runTimeFailureType = willRunTimeError(arg, fresh))
+                        reportError(CheckedFunctionCallError{argTypes[i], *runTimeFailureType, functionName, i}, arg->location);
+                }
+
+                if (call->args.size < argTypes.size())
+                {
+                    // We are passing fewer arguments than we expect
+                    // so we need to ensure that the rest of the args are optional.
+                    bool remainingArgsOptional = true;
+                    for (size_t i = call->args.size; i < argTypes.size(); i++)
+                        remainingArgsOptional = remainingArgsOptional && isOptional(argTypes[i]);
+                    if (!remainingArgsOptional)
+                    {
+                        reportError(CheckedFunctionIncorrectArgs{functionName, argTypes.size(), call->args.size}, call->location);
+                        return fresh;
+                    }
+                }
+            }
+        }
+
+        return fresh;
    }

-    NonStrictContext visit(AstExprIndexExpr* indexExpr, ValueContext context)
+    NonStrictContext visit(AstExprIndexName* indexName)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            NonStrictContext expr = visit(indexExpr->expr, context);
-            NonStrictContext index = visit(indexExpr->index, ValueContext::RValue);
-            return NonStrictContext::disjunction(builtinTypes, arena, expr, index);
-        }
-        else
-            return {};
+        return {};
+    }
+
+    NonStrictContext visit(AstExprIndexExpr* indexExpr)
+    {
+        return {};
    }

    NonStrictContext visit(AstExprFunction* exprFn)
@ -809,433 +780,47 @@ struct NonStrictTypeChecker
        for (AstLocal* local : exprFn->args)
        {
            if (std::optional<TypeId> ty = willRunTimeErrorFunctionDefinition(local, remainder))
-            {
-                const char* debugname = exprFn->debugname.value;
-                reportError(NonStrictFunctionDefinitionError{debugname ? debugname : "", local->name.value, *ty}, local->location);
-            }
+                reportError(NonStrictFunctionDefinitionError{exprFn->debugname.value, local->name.value, *ty}, local->location);
            remainder.remove(dfg->getDef(local));
-
-            if (FFlag::LuauNewNonStrictVisitTypes2)
-                visit(local->annotation);
        }
-
-        if (FFlag::LuauNewNonStrictVisitTypes2)
-        {
-            visitGenerics(exprFn->generics, exprFn->genericPacks);
-
-            if (FFlag::LuauStoreReturnTypesAsPackOnAst)
-                visit(exprFn->returnAnnotation);
-            else
-            {
-                if (exprFn->returnAnnotation_DEPRECATED)
-                    visit(*exprFn->returnAnnotation_DEPRECATED);
-            }
-
-            if (exprFn->varargAnnotation)
-                visit(exprFn->varargAnnotation);
-        }
-
        return remainder;
    }

    NonStrictContext visit(AstExprTable* table)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            for (auto [_, key, value] : table->items)
-            {
-                if (key)
-                    visit(key, ValueContext::RValue);
-                visit(value, ValueContext::RValue);
-            }
-        }
-
        return {};
    }

    NonStrictContext visit(AstExprUnary* unary)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-            return visit(unary->expr, ValueContext::RValue);
-        else
-            return {};
+        return {};
    }

    NonStrictContext visit(AstExprBinary* binary)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            NonStrictContext lhs = visit(binary->left, ValueContext::RValue);
-            NonStrictContext rhs = visit(binary->right, ValueContext::RValue);
-            return NonStrictContext::disjunction(builtinTypes, arena, lhs, rhs);
-        }
-        else
-            return {};
+        return {};
    }

    NonStrictContext visit(AstExprTypeAssertion* typeAssertion)
    {
-        if (FFlag::LuauNewNonStrictVisitTypes2)
-            visit(typeAssertion->annotation);
-
-        if (FFlag::LuauNonStrictVisitorImprovements)
-            return visit(typeAssertion->expr, ValueContext::RValue);
-        else
-            return {};
+        return {};
    }

    NonStrictContext visit(AstExprIfElse* ifElse)
    {
-        NonStrictContext condB = visit(ifElse->condition, ValueContext::RValue);
-        NonStrictContext thenB = visit(ifElse->trueExpr, ValueContext::RValue);
-        NonStrictContext elseB = visit(ifElse->falseExpr, ValueContext::RValue);
+        NonStrictContext condB = visit(ifElse->condition);
+        NonStrictContext thenB = visit(ifElse->trueExpr);
+        NonStrictContext elseB = visit(ifElse->falseExpr);
        return NonStrictContext::disjunction(builtinTypes, arena, condB, NonStrictContext::conjunction(builtinTypes, arena, thenB, elseB));
    }

    NonStrictContext visit(AstExprInterpString* interpString)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            for (AstExpr* expr : interpString->expressions)
-                visit(expr, ValueContext::RValue);
-        }
-
        return {};
    }

    NonStrictContext visit(AstExprError* error)
    {
-        if (FFlag::LuauNonStrictVisitorImprovements)
-        {
-            for (AstExpr* expr : error->expressions)
-                visit(expr, ValueContext::RValue);
-        }
-
-        return {};
-    }
-
-    void visit(AstType* ty)
-    {
-        LUAU_ASSERT(FFlag::LuauNewNonStrictVisitTypes2);
-
-        // If this node is `nullptr`, early exit.
-        if (!ty)
-            return;
-
-        if (auto t = ty->as<AstTypeReference>())
-            return visit(t);
-        else if (auto t = ty->as<AstTypeTable>())
-            return visit(t);
-        else if (auto t = ty->as<AstTypeFunction>())
-            return visit(t);
-        else if (auto t = ty->as<AstTypeTypeof>())
-            return visit(t);
-        else if (auto t = ty->as<AstTypeUnion>())
-            return visit(t);
-        else if (auto t = ty->as<AstTypeIntersection>())
-            return visit(t);
-        else if (auto t = ty->as<AstTypeGroup>())
-            return visit(t->type);
-    }
-
-    void visit(AstTypeReference* ty)
-    {
-        // No further validation is necessary in this case. The main logic for
-        // _luau_print is contained in lookupAnnotation.
-        if (FFlag::DebugLuauMagicTypes && ty->name == "_luau_print")
-            return;
-
-        for (const AstTypeOrPack& param : ty->parameters)
-        {
-            if (param.type)
-                visit(param.type);
-            else
-                visit(param.typePack);
-        }
-
-        Scope* scope = findInnermostScope(ty->location);
-        LUAU_ASSERT(scope);
-
-        std::optional<TypeFun> alias = ty->prefix ? scope->lookupImportedType(ty->prefix->value, ty->name.value) : scope->lookupType(ty->name.value);
-
-        if (alias.has_value())
-        {
-            size_t typesRequired = alias->typeParams.size();
-            size_t packsRequired = alias->typePackParams.size();
-
-            bool hasDefaultTypes = std::any_of(
-                alias->typeParams.begin(),
-                alias->typeParams.end(),
-                [](auto&& el)
-                {
-                    return el.defaultValue.has_value();
-                }
-            );
-
-            bool hasDefaultPacks = std::any_of(
-                alias->typePackParams.begin(),
-                alias->typePackParams.end(),
-                [](auto&& el)
-                {
-                    return el.defaultValue.has_value();
-                }
-            );
-
-            if (!ty->hasParameterList)
-            {
-                if ((!alias->typeParams.empty() && !hasDefaultTypes) || (!alias->typePackParams.empty() && !hasDefaultPacks))
-                    reportError(GenericError{"Type parameter list is required"}, ty->location);
-            }
-
-            size_t typesProvided = 0;
-            size_t extraTypes = 0;
-            size_t packsProvided = 0;
-
-            for (const AstTypeOrPack& p : ty->parameters)
-            {
-                if (p.type)
-                {
-                    if (packsProvided != 0)
-                    {
-                        reportError(GenericError{"Type parameters must come before type pack parameters"}, ty->location);
-                        continue;
-                    }
-
-                    if (typesProvided < typesRequired)
-                        typesProvided += 1;
-                    else
-                        extraTypes += 1;
-                }
-                else if (p.typePack)
-                {
-                    std::optional<TypePackId> tp = lookupPackAnnotation(p.typePack);
-                    if (!tp.has_value())
-                        continue;
-
-                    if (typesProvided < typesRequired && size(*tp) == 1 && finite(*tp) && first(*tp))
-                        typesProvided += 1;
-                    else
-                        packsProvided += 1;
-                }
-            }
-
-            if (extraTypes != 0 && packsProvided == 0)
-            {
-                // Extra types are only collected into a pack if a pack is expected
-                if (packsRequired != 0)
-                    packsProvided += 1;
-                else
-                    typesProvided += extraTypes;
-            }
-
-            for (size_t i = typesProvided; i < typesRequired; ++i)
-            {
-                if (alias->typeParams[i].defaultValue)
-                    typesProvided += 1;
-            }
-
-            for (size_t i = packsProvided; i < packsRequired; ++i)
-            {
-                if (alias->typePackParams[i].defaultValue)
-                    packsProvided += 1;
-            }
-
-            if (extraTypes == 0 && packsProvided + 1 == packsRequired)
-                packsProvided += 1;
-
-
-            if (typesProvided != typesRequired || packsProvided != packsRequired)
-            {
-                reportError(
-                    IncorrectGenericParameterCount{
-                        /* name */ ty->name.value,
-                        /* typeFun */ *alias,
-                        /* actualParameters */ typesProvided,
-                        /* actualPackParameters */ packsProvided,
-                    },
-                    ty->location
-                );
-            }
-        }
-        else
-        {
-            if (scope->lookupPack(ty->name.value))
-            {
-                reportError(
-                    SwappedGenericTypeParameter{
-                        ty->name.value,
-                        SwappedGenericTypeParameter::Kind::Type,
-                    },
-                    ty->location
-                );
-            }
-            else
-            {
-                std::string symbol = "";
-                if (ty->prefix)
-                {
-                    symbol += (*(ty->prefix)).value;
-                    symbol += ".";
-                }
-                symbol += ty->name.value;
-
-                reportError(UnknownSymbol{symbol, UnknownSymbol::Context::Type}, ty->location);
-            }
-        }
-    }
-
-    void visit(AstTypeTable* table)
-    {
-        if (table->indexer)
-        {
-            visit(table->indexer->indexType);
-            visit(table->indexer->resultType);
-        }
-
-        for (auto prop : table->props)
-            visit(prop.type);
-    }
-
-    void visit(AstTypeFunction* function)
-    {
-        visit(function->argTypes);
-        visit(function->returnTypes);
-    }
-
-    void visit(AstTypeTypeof* typeOf)
-    {
-        visit(typeOf->expr, ValueContext::RValue);
-    }
-
-    void visit(AstTypeUnion* unionType)
-    {
-        for (auto typ : unionType->types)
-            visit(typ);
-    }
-
-    void visit(AstTypeIntersection* intersectionType)
-    {
-        for (auto typ : intersectionType->types)
-            visit(typ);
-    }
-
-    void visit(AstTypeList& list)
-    {
-        for (auto typ : list.types)
-            visit(typ);
-        if (list.tailType)
-            visit(list.tailType);
-    }
-
-    void visit(AstTypePack* pack)
-    {
-        LUAU_ASSERT(FFlag::LuauNewNonStrictVisitTypes2);
-
-        // If there is no pack node, early exit.
-        if (!pack)
-            return;
-
-        if (auto p = pack->as<AstTypePackExplicit>())
-            return visit(p);
-        else if (auto p = pack->as<AstTypePackVariadic>())
-            return visit(p);
-        else if (auto p = pack->as<AstTypePackGeneric>())
-            return visit(p);
-    }
-
-    void visit(AstTypePackExplicit* tp)
-    {
-        for (AstType* type : tp->typeList.types)
-            visit(type);
-
-        if (tp->typeList.tailType)
-            visit(tp->typeList.tailType);
-    }
-
-    void visit(AstTypePackVariadic* tp)
-    {
-        visit(tp->variadicType);
-    }
-
-    void visit(AstTypePackGeneric* tp)
-    {
-        Scope* scope = findInnermostScope(tp->location);
-        LUAU_ASSERT(scope);
-
-        std::optional<TypePackId> alias = scope->lookupPack(tp->genericName.value);
-        if (!alias.has_value())
-        {
-            if (scope->lookupType(tp->genericName.value))
-            {
-                reportError(
-                    SwappedGenericTypeParameter{
-                        tp->genericName.value,
-                        SwappedGenericTypeParameter::Kind::Pack,
-                    },
-                    tp->location
-                );
-            }
-        }
-        else
-        {
-            reportError(UnknownSymbol{tp->genericName.value, UnknownSymbol::Context::Type}, tp->location);
-        }
-    }
-
-    void visitGenerics(AstArray<AstGenericType*> generics, AstArray<AstGenericTypePack*> genericPacks)
-    {
-        DenseHashSet<AstName> seen{AstName{}};
-
-        for (const auto* g : generics)
-        {
-            if (seen.contains(g->name))
-                reportError(DuplicateGenericParameter{g->name.value}, g->location);
-            else
-                seen.insert(g->name);
-
-            if (g->defaultValue)
-                visit(g->defaultValue);
-        }
-
-        for (const auto* g : genericPacks)
-        {
-            if (seen.contains(g->name))
-                reportError(DuplicateGenericParameter{g->name.value}, g->location);
-            else
-                seen.insert(g->name);
-
-            if (g->defaultValue)
-                visit(g->defaultValue);
-        }
-    }
-
-    Scope* findInnermostScope(Location location) const
-    {
-        Scope* bestScope = module->getModuleScope().get();
-
-        bool didNarrow;
-        do
-        {
-            didNarrow = false;
-            for (auto scope : bestScope->children)
-            {
-                if (scope->location.encloses(location))
-                {
-                    bestScope = scope.get();
-                    didNarrow = true;
-                    break;
-                }
-            }
-        } while (didNarrow && bestScope->children.size() > 0);
-
-        return bestScope;
-    }
-
-    std::optional<TypePackId> lookupPackAnnotation(AstTypePack* annotation) const
-    {
-        TypePackId* tp = module->astResolvedTypePacks.find(annotation);
-        if (tp != nullptr)
-            return {follow(*tp)};
        return {};
    }

--- a/Analysis/src/Normalize.cpp
+++ b/Analysis/src/Normalize.cpp
@ -17,12 +17,12 @@

 LUAU_FASTFLAGVARIABLE(DebugLuauCheckNormalizeInvariant)

-LUAU_FASTINTVARIABLE(LuauNormalizeCacheLimit, 100000)
+LUAU_FASTINTVARIABLE(LuauNormalizeCacheLimit, 100000);
+LUAU_FASTFLAG(LuauSolverV2);
+
 LUAU_FASTINTVARIABLE(LuauNormalizeIntersectionLimit, 200)
-LUAU_FASTINTVARIABLE(LuauNormalizeUnionLimit, 100)
-LUAU_FASTFLAG(LuauSolverV2)
-LUAU_FASTFLAGVARIABLE(LuauFixInfiniteRecursionInNormalization)
-LUAU_FASTFLAGVARIABLE(LuauNormalizationCatchMetatableCycles)
+LUAU_FASTFLAGVARIABLE(LuauNormalizationTracksCyclicPairsThroughInhabitance);
+LUAU_FASTFLAGVARIABLE(LuauIntersectNormalsNeedsToTrackResourceLimits);

 namespace Luau
 {
@ -249,23 +249,23 @@ bool isSubtype(const NormalizedStringType& subStr, const NormalizedStringType& s
    return true;
 }

-void NormalizedExternType::pushPair(TypeId ty, TypeIds negations)
+void NormalizedClassType::pushPair(TypeId ty, TypeIds negations)
 {
-    auto result = externTypes.insert(std::make_pair(ty, std::move(negations)));
+    auto result = classes.insert(std::make_pair(ty, std::move(negations)));
    if (result.second)
        ordering.push_back(ty);
-    LUAU_ASSERT(ordering.size() == externTypes.size());
+    LUAU_ASSERT(ordering.size() == classes.size());
 }

-void NormalizedExternType::resetToNever()
+void NormalizedClassType::resetToNever()
 {
    ordering.clear();
-    externTypes.clear();
+    classes.clear();
 }

-bool NormalizedExternType::isNever() const
+bool NormalizedClassType::isNever() const
 {
-    return externTypes.empty();
+    return classes.empty();
 }

 void NormalizedFunctionType::resetToTop()
@ -304,17 +304,17 @@ bool NormalizedType::isUnknown() const

    // Otherwise, we can still be unknown!
    bool hasAllPrimitives = isPrim(booleans, PrimitiveType::Boolean) && isPrim(nils, PrimitiveType::NilType) && isNumber(numbers) &&
-                            strings.isString() && isThread(threads) && isBuffer(buffers);
+                            strings.isString() && isPrim(threads, PrimitiveType::Thread) && isThread(threads);

    // Check is class
-    bool isTopExternType = false;
-    for (const auto& [t, disj] : externTypes.externTypes)
+    bool isTopClass = false;
+    for (auto [t, disj] : classes.classes)
    {
-        if (auto ct = get<ExternType>(t))
+        if (auto ct = get<ClassType>(t))
        {
            if (ct->name == "class" && disj.empty())
            {
-                isTopExternType = true;
+                isTopClass = true;
                break;
            }
        }
@ -330,24 +330,24 @@ bool NormalizedType::isUnknown() const
        }
    }
    // any = unknown or error ==> we need to make sure we have all the unknown components, but not errors
-    return get<NeverType>(errors) && hasAllPrimitives && isTopExternType && isTopTable && functions.isTop;
+    return get<NeverType>(errors) && hasAllPrimitives && isTopClass && isTopTable && functions.isTop;
 }

 bool NormalizedType::isExactlyNumber() const
 {
-    return hasNumbers() && !hasTops() && !hasBooleans() && !hasExternTypes() && !hasErrors() && !hasNils() && !hasStrings() && !hasThreads() &&
+    return hasNumbers() && !hasTops() && !hasBooleans() && !hasClasses() && !hasErrors() && !hasNils() && !hasStrings() && !hasThreads() &&
           !hasBuffers() && !hasTables() && !hasFunctions() && !hasTyvars();
 }

 bool NormalizedType::isSubtypeOfString() const
 {
-    return hasStrings() && !hasTops() && !hasBooleans() && !hasExternTypes() && !hasErrors() && !hasNils() && !hasNumbers() && !hasThreads() &&
+    return hasStrings() && !hasTops() && !hasBooleans() && !hasClasses() && !hasErrors() && !hasNils() && !hasNumbers() && !hasThreads() &&
           !hasBuffers() && !hasTables() && !hasFunctions() && !hasTyvars();
 }

 bool NormalizedType::isSubtypeOfBooleans() const
 {
-    return hasBooleans() && !hasTops() && !hasExternTypes() && !hasErrors() && !hasNils() && !hasNumbers() && !hasStrings() && !hasThreads() &&
+    return hasBooleans() && !hasTops() && !hasClasses() && !hasErrors() && !hasNils() && !hasNumbers() && !hasStrings() && !hasThreads() &&
           !hasBuffers() && !hasTables() && !hasFunctions() && !hasTyvars();
 }

@ -380,9 +380,9 @@ bool NormalizedType::hasBooleans() const
    return !get<NeverType>(booleans);
 }

-bool NormalizedType::hasExternTypes() const
+bool NormalizedType::hasClasses() const
 {
-    return !externTypes.isNever();
+    return !classes.isNever();
 }

 bool NormalizedType::hasErrors() const
@ -440,7 +440,7 @@ bool NormalizedType::isFalsy() const
            hasAFalse = !bs->value;
    }

-    return (hasAFalse || hasNils()) && (!hasTops() && !hasExternTypes() && !hasErrors() && !hasNumbers() && !hasStrings() && !hasThreads() &&
+    return (hasAFalse || hasNils()) && (!hasTops() && !hasClasses() && !hasErrors() && !hasNumbers() && !hasStrings() && !hasThreads() &&
                                        !hasBuffers() && !hasTables() && !hasFunctions() && !hasTyvars());
 }

@ -452,7 +452,7 @@ bool NormalizedType::isTruthy() const
 static bool isShallowInhabited(const NormalizedType& norm)
 {
    // This test is just a shallow check, for example it returns `true` for `{ p : never }`
-    return !get<NeverType>(norm.tops) || !get<NeverType>(norm.booleans) || !norm.externTypes.isNever() || !get<NeverType>(norm.errors) ||
+    return !get<NeverType>(norm.tops) || !get<NeverType>(norm.booleans) || !norm.classes.isNever() || !get<NeverType>(norm.errors) ||
           !get<NeverType>(norm.nils) || !get<NeverType>(norm.numbers) || !norm.strings.isNever() || !get<NeverType>(norm.threads) ||
           !get<NeverType>(norm.buffers) || !norm.functions.isNever() || !norm.tables.empty() || !norm.tyvars.empty();
 }
@ -471,7 +471,7 @@ NormalizationResult Normalizer::isInhabited(const NormalizedType* norm, Set<Type
        return NormalizationResult::HitLimits;

    if (!get<NeverType>(norm->tops) || !get<NeverType>(norm->booleans) || !get<NeverType>(norm->errors) || !get<NeverType>(norm->nils) ||
-        !get<NeverType>(norm->numbers) || !get<NeverType>(norm->threads) || !get<NeverType>(norm->buffers) || !norm->externTypes.isNever() ||
+        !get<NeverType>(norm->numbers) || !get<NeverType>(norm->threads) || !get<NeverType>(norm->buffers) || !norm->classes.isNever() ||
        !norm->strings.isNever() || !norm->functions.isNever())
        return NormalizationResult::True;

@ -579,7 +579,7 @@ NormalizationResult Normalizer::isIntersectionInhabited(TypeId left, TypeId righ
 {
    left = follow(left);
    right = follow(right);
-    // We're asking if intersection is inhabited between left and right but we've already seen them ....
+    // We're asking if intersection is inahbited between left and right but we've already seen them ....

    if (cacheInhabitance)
    {
@ -619,13 +619,13 @@ static int tyvarIndex(TypeId ty)
        return 0;
 }

-static bool isTop(NotNull<BuiltinTypes> builtinTypes, const NormalizedExternType& externTypes)
+static bool isTop(NotNull<BuiltinTypes> builtinTypes, const NormalizedClassType& classes)
 {
-    if (externTypes.externTypes.size() != 1)
+    if (classes.classes.size() != 1)
        return false;

-    auto first = externTypes.externTypes.begin();
-    if (first->first != builtinTypes->externType)
+    auto first = classes.classes.begin();
+    if (first->first != builtinTypes->classType)
        return false;

    if (!first->second.empty())
@ -634,11 +634,11 @@ static bool isTop(NotNull<BuiltinTypes> builtinTypes, const NormalizedExternType
    return true;
 }

-static void resetToTop(NotNull<BuiltinTypes> builtinTypes, NormalizedExternType& externTypes)
+static void resetToTop(NotNull<BuiltinTypes> builtinTypes, NormalizedClassType& classes)
 {
-    externTypes.ordering.clear();
-    externTypes.externTypes.clear();
-    externTypes.pushPair(builtinTypes->externType, TypeIds{});
+    classes.ordering.clear();
+    classes.classes.clear();
+    classes.pushPair(builtinTypes->classType, TypeIds{});
 }

 #ifdef LUAU_ASSERTENABLED
@ -762,50 +762,50 @@ static bool areNormalizedTables(const TypeIds& tys)
    return true;
 }

-static bool areNormalizedExternTypes(const NormalizedExternType& tys)
+static bool areNormalizedClasses(const NormalizedClassType& tys)
 {
-    for (const auto& [ty, negations] : tys.externTypes)
+    for (const auto& [ty, negations] : tys.classes)
    {
-        const ExternType* etv = get<ExternType>(ty);
-        if (!etv)
+        const ClassType* ctv = get<ClassType>(ty);
+        if (!ctv)
        {
            return false;
        }

        for (TypeId negation : negations)
        {
-            const ExternType* nctv = get<ExternType>(negation);
+            const ClassType* nctv = get<ClassType>(negation);
            if (!nctv)
            {
                return false;
            }

-            if (!isSubclass(nctv, etv))
+            if (!isSubclass(nctv, ctv))
            {
                return false;
            }
        }

-        for (const auto& [otherTy, otherNegations] : tys.externTypes)
+        for (const auto& [otherTy, otherNegations] : tys.classes)
        {
            if (otherTy == ty)
                continue;

-            const ExternType* octv = get<ExternType>(otherTy);
+            const ClassType* octv = get<ClassType>(otherTy);
            if (!octv)
            {
                return false;
            }

-            if (isSubclass(etv, octv))
+            if (isSubclass(ctv, octv))
            {
-                auto iss = [etv](TypeId t)
+                auto iss = [ctv](TypeId t)
                {
-                    const ExternType* c = get<ExternType>(t);
+                    const ClassType* c = get<ClassType>(t);
                    if (!c)
                        return false;

-                    return isSubclass(etv, c);
+                    return isSubclass(ctv, c);
                };

                if (!std::any_of(otherNegations.begin(), otherNegations.end(), iss))
@ -847,7 +847,7 @@ static void assertInvariant(const NormalizedType& norm)

    LUAU_ASSERT(isNormalizedTop(norm.tops));
    LUAU_ASSERT(isNormalizedBoolean(norm.booleans));
-    LUAU_ASSERT(areNormalizedExternTypes(norm.externTypes));
+    LUAU_ASSERT(areNormalizedClasses(norm.classes));
    LUAU_ASSERT(isNormalizedError(norm.errors));
    LUAU_ASSERT(isNormalizedNil(norm.nils));
    LUAU_ASSERT(isNormalizedNumber(norm.numbers));
@ -988,7 +988,7 @@ void Normalizer::clearNormal(NormalizedType& norm)
 {
    norm.tops = builtinTypes->neverType;
    norm.booleans = builtinTypes->neverType;
-    norm.externTypes.resetToNever();
+    norm.classes.resetToNever();
    norm.errors = builtinTypes->neverType;
    norm.nils = builtinTypes->neverType;
    norm.numbers = builtinTypes->neverType;
@ -1138,17 +1138,17 @@ TypeId Normalizer::unionOfBools(TypeId here, TypeId there)
    return builtinTypes->booleanType;
 }

-void Normalizer::unionExternTypesWithExternType(TypeIds& heres, TypeId there)
+void Normalizer::unionClassesWithClass(TypeIds& heres, TypeId there)
 {
    if (heres.count(there))
        return;

-    const ExternType* tctv = get<ExternType>(there);
+    const ClassType* tctv = get<ClassType>(there);

    for (auto it = heres.begin(); it != heres.end();)
    {
        TypeId here = *it;
-        const ExternType* hctv = get<ExternType>(here);
+        const ClassType* hctv = get<ClassType>(here);
        if (isSubclass(tctv, hctv))
            return;
        else if (isSubclass(hctv, tctv))
@ -1160,16 +1160,16 @@ void Normalizer::unionExternTypesWithExternType(TypeIds& heres, TypeId there)
    heres.insert(there);
 }

-void Normalizer::unionExternTypes(TypeIds& heres, const TypeIds& theres)
+void Normalizer::unionClasses(TypeIds& heres, const TypeIds& theres)
 {
    for (TypeId there : theres)
-        unionExternTypesWithExternType(heres, there);
+        unionClassesWithClass(heres, there);
 }

 static bool isSubclass(TypeId test, TypeId parent)
 {
-    const ExternType* testCtv = get<ExternType>(test);
-    const ExternType* parentCtv = get<ExternType>(parent);
+    const ClassType* testCtv = get<ClassType>(test);
+    const ClassType* parentCtv = get<ClassType>(parent);

    LUAU_ASSERT(testCtv);
    LUAU_ASSERT(parentCtv);
@ -1177,12 +1177,12 @@ static bool isSubclass(TypeId test, TypeId parent)
    return isSubclass(testCtv, parentCtv);
 }

-void Normalizer::unionExternTypesWithExternType(NormalizedExternType& heres, TypeId there)
+void Normalizer::unionClassesWithClass(NormalizedClassType& heres, TypeId there)
 {
    for (auto it = heres.ordering.begin(); it != heres.ordering.end();)
    {
        TypeId hereTy = *it;
-        TypeIds& hereNegations = heres.externTypes.at(hereTy);
+        TypeIds& hereNegations = heres.classes.at(hereTy);

        // If the incoming class is a subclass of another class in the map, we
        // must ensure that it is negated by one of the negations in the same
@ -1204,7 +1204,7 @@ void Normalizer::unionExternTypesWithExternType(NormalizedExternType& heres, Typ
                }
                // If the incoming class is a superclass of one of the
                // negations, then the negation no longer applies and must be
-                // removed. This is also true if they are equal. Since extern types
+                // removed. This is also true if they are equal. Since classes
                // are, at this time, entirely persistent (we do not clone
                // them), a pointer identity check is sufficient.
                else if (isSubclass(hereNegation, there))
@ -1231,7 +1231,7 @@ void Normalizer::unionExternTypesWithExternType(NormalizedExternType& heres, Typ
        {
            TypeIds negations = std::move(hereNegations);
            it = heres.ordering.erase(it);
-            heres.externTypes.erase(hereTy);
+            heres.classes.erase(hereTy);

            heres.pushPair(there, std::move(negations));
            return;
@ -1248,10 +1248,10 @@ void Normalizer::unionExternTypesWithExternType(NormalizedExternType& heres, Typ
    heres.pushPair(there, TypeIds{});
 }

-void Normalizer::unionExternTypes(NormalizedExternType& heres, const NormalizedExternType& theres)
+void Normalizer::unionClasses(NormalizedClassType& heres, const NormalizedClassType& theres)
 {
-    // This method bears much similarity with unionExternTypesWithExternType, but is
-    // solving a more general problem. In unionExternTypesWithExternType, we are dealing
+    // This method bears much similarity with unionClassesWithClass, but is
+    // solving a more general problem. In unionClassesWithClass, we are dealing
    // with a singular positive type. Since it's one type, we can use early
    // returns as control flow. Since it's guaranteed to be positive, we do not
    // have negations to worry about combining. The two aspects combine to make
@ -1260,9 +1260,9 @@ void Normalizer::unionExternTypes(NormalizedExternType& heres, const NormalizedE

    for (const TypeId thereTy : theres.ordering)
    {
-        const TypeIds& thereNegations = theres.externTypes.at(thereTy);
+        const TypeIds& thereNegations = theres.classes.at(thereTy);

-        // If it happens that there are _no_ extern types in the current map, or the
+        // If it happens that there are _no_ classes in the current map, or the
        // incoming class is completely unrelated to any class in the current
        // map, we must insert the incoming pair as-is.
        bool insert = true;
@ -1270,7 +1270,7 @@ void Normalizer::unionExternTypes(NormalizedExternType& heres, const NormalizedE
        for (auto it = heres.ordering.begin(); it != heres.ordering.end();)
        {
            TypeId hereTy = *it;
-            TypeIds& hereNegations = heres.externTypes.at(hereTy);
+            TypeIds& hereNegations = heres.classes.at(hereTy);

            if (isSubclass(thereTy, hereTy))
            {
@ -1294,7 +1294,7 @@ void Normalizer::unionExternTypes(NormalizedExternType& heres, const NormalizedE
                    // If the incoming class is a superclass of one of the
                    // negations, then the negation no longer applies and must
                    // be removed. This is also true if they are equal. Since
-                    // extern types are, at this time, entirely persistent (we do not
+                    // classes are, at this time, entirely persistent (we do not
                    // clone them), a pointer identity check is sufficient.
                    else if (isSubclass(hereNegateTy, thereTy))
                    {
@ -1319,17 +1319,17 @@ void Normalizer::unionExternTypes(NormalizedExternType& heres, const NormalizedE
            else if (isSubclass(hereTy, thereTy))
            {
                TypeIds negations = std::move(hereNegations);
-                unionExternTypes(negations, thereNegations);
+                unionClasses(negations, thereNegations);

                it = heres.ordering.erase(it);
-                heres.externTypes.erase(hereTy);
+                heres.classes.erase(hereTy);
                heres.pushPair(thereTy, std::move(negations));
                insert = false;
                break;
            }
            else if (hereTy == thereTy)
            {
-                unionExternTypes(hereNegations, thereNegations);
+                unionClasses(hereNegations, thereNegations);
                insert = false;
                break;
            }
@ -1685,12 +1685,8 @@ NormalizationResult Normalizer::unionNormals(NormalizedType& here, const Normali
            return res;
    }

-    // Limit based on worst-case expansion of the function unions
-    if (here.functions.parts.size() * there.functions.parts.size() >= size_t(FInt::LuauNormalizeUnionLimit))
-        return NormalizationResult::HitLimits;
-
    here.booleans = unionOfBools(here.booleans, there.booleans);
-    unionExternTypes(here.externTypes, there.externTypes);
+    unionClasses(here.classes, there.classes);

    here.errors = (get<NeverType>(there.errors) ? here.errors : there.errors);
    here.nils = (get<NeverType>(there.nils) ? here.nils : there.nils);
@ -1700,7 +1696,6 @@ NormalizationResult Normalizer::unionNormals(NormalizedType& here, const Normali
    here.buffers = (get<NeverType>(there.buffers) ? here.buffers : there.buffers);
    unionFunctions(here.functions, there.functions);
    unionTables(here.tables, there.tables);
-
    return NormalizationResult::True;
 }

@ -1740,7 +1735,7 @@ NormalizationResult Normalizer::intersectNormalWithNegationTy(TypeId toNegate, N
    return NormalizationResult::True;
 }

-// See above for an explanation of `ignoreSmallerTyvars`.
+// See above for an explaination of `ignoreSmallerTyvars`.
 NormalizationResult Normalizer::unionNormalWithTy(
    NormalizedType& here,
    TypeId there,
@ -1830,8 +1825,8 @@ NormalizationResult Normalizer::unionNormalWithTy(
        unionFunctionsWithFunction(here.functions, there);
    else if (get<TableType>(there) || get<MetatableType>(there))
        unionTablesWithTable(here.tables, there);
-    else if (get<ExternType>(there))
-        unionExternTypesWithExternType(here.externTypes, there);
+    else if (get<ClassType>(there))
+        unionClassesWithClass(here.classes, there);
    else if (get<ErrorType>(there))
        here.errors = there;
    else if (const PrimitiveType* ptv = get<PrimitiveType>(there))
@ -1944,29 +1939,29 @@ std::optional<NormalizedType> Normalizer::negateNormal(const NormalizedType& her
            result.booleans = builtinTypes->trueType;
    }

-    if (here.externTypes.isNever())
+    if (here.classes.isNever())
    {
-        resetToTop(builtinTypes, result.externTypes);
+        resetToTop(builtinTypes, result.classes);
    }
-    else if (isTop(builtinTypes, result.externTypes))
+    else if (isTop(builtinTypes, result.classes))
    {
-        result.externTypes.resetToNever();
+        result.classes.resetToNever();
    }
    else
    {
        TypeIds rootNegations{};

-        for (const auto& [hereParent, hereNegations] : here.externTypes.externTypes)
+        for (const auto& [hereParent, hereNegations] : here.classes.classes)
        {
-            if (hereParent != builtinTypes->externType)
+            if (hereParent != builtinTypes->classType)
                rootNegations.insert(hereParent);

            for (TypeId hereNegation : hereNegations)
-                unionExternTypesWithExternType(result.externTypes, hereNegation);
+                unionClassesWithClass(result.classes, hereNegation);
        }

        if (!rootNegations.empty())
-            result.externTypes.pushPair(builtinTypes->externType, rootNegations);
+            result.classes.pushPair(builtinTypes->classType, rootNegations);
    }

    result.nils = get<NeverType>(here.nils) ? builtinTypes->nilType : builtinTypes->neverType;
@ -2144,7 +2139,7 @@ TypeId Normalizer::intersectionOfBools(TypeId here, TypeId there)
        return there;
 }

-void Normalizer::intersectExternTypes(NormalizedExternType& heres, const NormalizedExternType& theres)
+void Normalizer::intersectClasses(NormalizedClassType& heres, const NormalizedClassType& theres)
 {
    if (theres.isNever())
    {
@ -2178,12 +2173,12 @@ void Normalizer::intersectExternTypes(NormalizedExternType& heres, const Normali
    //   declare the result of the intersection operation to be never.
    for (const TypeId thereTy : theres.ordering)
    {
-        const TypeIds& thereNegations = theres.externTypes.at(thereTy);
+        const TypeIds& thereNegations = theres.classes.at(thereTy);

        for (auto it = heres.ordering.begin(); it != heres.ordering.end();)
        {
            TypeId hereTy = *it;
-            TypeIds& hereNegations = heres.externTypes.at(hereTy);
+            TypeIds& hereNegations = heres.classes.at(hereTy);

            if (isSubclass(thereTy, hereTy))
            {
@ -2206,10 +2201,10 @@ void Normalizer::intersectExternTypes(NormalizedExternType& heres, const Normali
                    }
                }

-                unionExternTypes(negations, thereNegations);
+                unionClasses(negations, thereNegations);

                it = heres.ordering.erase(it);
-                heres.externTypes.erase(hereTy);
+                heres.classes.erase(hereTy);
                heres.pushPair(thereTy, std::move(negations));
                break;
            }
@ -2234,15 +2229,15 @@ void Normalizer::intersectExternTypes(NormalizedExternType& heres, const Normali
                {
                    if (isSubclass(hereTy, *nIt))
                    {
-                        // eg SomeExternType & (class & ~SomeExternType)
-                        // or SomeExternType & (class & ~ParentExternType)
-                        heres.externTypes.erase(hereTy);
+                        // eg SomeClass & (class & ~SomeClass)
+                        // or SomeClass & (class & ~ParentClass)
+                        heres.classes.erase(hereTy);
                        it = heres.ordering.erase(it);
                        erasedHere = true;
                        break;
                    }

-                    // eg SomeExternType & (class & ~Unrelated)
+                    // eg SomeClass & (class & ~Unrelated)
                    if (!isSubclass(*nIt, hereTy))
                        nIt = negations.erase(nIt);
                    else
@ -2251,30 +2246,30 @@ void Normalizer::intersectExternTypes(NormalizedExternType& heres, const Normali

                if (!erasedHere)
                {
-                    unionExternTypes(hereNegations, negations);
+                    unionClasses(hereNegations, negations);
                    ++it;
                }
            }
            else if (hereTy == thereTy)
            {
-                unionExternTypes(hereNegations, thereNegations);
+                unionClasses(hereNegations, thereNegations);
                break;
            }
            else
            {
                it = heres.ordering.erase(it);
-                heres.externTypes.erase(hereTy);
+                heres.classes.erase(hereTy);
            }
        }
    }
 }

-void Normalizer::intersectExternTypesWithExternType(NormalizedExternType& heres, TypeId there)
+void Normalizer::intersectClassesWithClass(NormalizedClassType& heres, TypeId there)
 {
    for (auto it = heres.ordering.begin(); it != heres.ordering.end();)
    {
        TypeId hereTy = *it;
-        const TypeIds& hereNegations = heres.externTypes.at(hereTy);
+        const TypeIds& hereNegations = heres.classes.at(hereTy);

        // If the incoming class _is_ the current class, we skip it. Maybe
        // another entry will have a different story. We check for this first
@ -2290,24 +2285,9 @@ void Normalizer::intersectExternTypesWithExternType(NormalizedExternType& heres,
        else if (isSubclass(there, hereTy))
        {
            TypeIds negations = std::move(hereNegations);
-            bool emptyIntersectWithNegation = false;

            for (auto nIt = negations.begin(); nIt != negations.end();)
            {
-                if (isSubclass(there, *nIt))
-                {
-                    // Hitting this block means that the incoming class is a
-                    // subclass of this type, _and_ one of its negations is a
-                    // superclass of this type, e.g.:
-                    //
-                    //  Dog & ~Animal
-                    //
-                    // Clearly this intersects to never, so we mark this class as
-                    // being removed from the normalized class type.
-                    emptyIntersectWithNegation = true;
-                    break;
-                }
-
                if (!isSubclass(*nIt, there))
                {
                    nIt = negations.erase(nIt);
@ -2319,9 +2299,8 @@ void Normalizer::intersectExternTypesWithExternType(NormalizedExternType& heres,
            }

            it = heres.ordering.erase(it);
-            heres.externTypes.erase(hereTy);
-            if (!emptyIntersectWithNegation)
-                heres.pushPair(there, std::move(negations));
+            heres.classes.erase(hereTy);
+            heres.pushPair(there, std::move(negations));
            break;
        }
        // If the incoming class is a superclass of the current class, we don't
@ -2335,7 +2314,7 @@ void Normalizer::intersectExternTypesWithExternType(NormalizedExternType& heres,
        else
        {
            it = heres.ordering.erase(it);
-            heres.externTypes.erase(hereTy);
+            heres.classes.erase(hereTy);
        }
    }
 }
@ -2606,31 +2585,11 @@ std::optional<TypeId> Normalizer::intersectionOfTables(TypeId here, TypeId there
                {
                    if (tprop.readTy.has_value())
                    {
-                        if (FFlag::LuauFixInfiniteRecursionInNormalization)
+                        // if the intersection of the read types of a property is uninhabited, the whole table is `never`.
+                        // We've seen these table prop elements before and we're about to ask if their intersection
+                        // is inhabited
+                        if (FFlag::LuauNormalizationTracksCyclicPairsThroughInhabitance)
                        {
-                            TypeId ty = simplifyIntersection(builtinTypes, NotNull{arena}, *hprop.readTy, *tprop.readTy).result;
-
-                            // If any property is going to get mapped to `never`, we can just call the entire table `never`.
-                            // Since this check is syntactic, we may sometimes miss simplifying tables with complex uninhabited properties.
-                            // Prior versions of this code attempted to do this semantically using the normalization machinery, but this
-                            // mistakenly causes infinite loops when giving more complex recursive table types. As it stands, this approach
-                            // will continue to scale as simplification is improved, but we may wish to reintroduce the semantic approach
-                            // once we have revisited the usage of seen sets systematically (and possibly with some additional guarding to recognize
-                            // when types are infinitely-recursive with non-pointer identical instances of them, or some guard to prevent that
-                            // construction altogether). See also: `gh1632_no_infinite_recursion_in_normalization`
-                            if (get<NeverType>(ty))
-                                return {builtinTypes->neverType};
-
-                            prop.readTy = ty;
-                            hereSubThere &= (ty == hprop.readTy);
-                            thereSubHere &= (ty == tprop.readTy);
-                        }
-                        else
-                        {
-                            // if the intersection of the read types of a property is uninhabited, the whole table is `never`.
-                            // We've seen these table prop elements before and we're about to ask if their intersection
-                            // is inhabited
-
                            auto pair1 = std::pair{*hprop.readTy, *tprop.readTy};
                            auto pair2 = std::pair{*tprop.readTy, *hprop.readTy};
                            if (seenTablePropPairs.contains(pair1) || seenTablePropPairs.contains(pair2))
@ -2645,8 +2604,6 @@ std::optional<TypeId> Normalizer::intersectionOfTables(TypeId here, TypeId there
                                seenTablePropPairs.insert(pair2);
                            }

-                            // FIXME(ariel): this is being added in a flag removal, so not changing the semantics here, but worth noting that this
-                            // fresh `seenSet` is definitely a bug. we already have `seenSet` from the parameter that _should_ have been used here.
                            Set<TypeId> seenSet{nullptr};
                            NormalizationResult res = isIntersectionInhabited(*hprop.readTy, *tprop.readTy, seenTablePropPairs, seenSet);

@ -2660,6 +2617,34 @@ std::optional<TypeId> Normalizer::intersectionOfTables(TypeId here, TypeId there
                            hereSubThere &= (ty == hprop.readTy);
                            thereSubHere &= (ty == tprop.readTy);
                        }
+                        else
+                        {
+
+                            if (seenSet.contains(*hprop.readTy) && seenSet.contains(*tprop.readTy))
+                            {
+                                seenSet.erase(*hprop.readTy);
+                                seenSet.erase(*tprop.readTy);
+                                return {builtinTypes->neverType};
+                            }
+                            else
+                            {
+                                seenSet.insert(*hprop.readTy);
+                                seenSet.insert(*tprop.readTy);
+                            }
+
+                            NormalizationResult res = isIntersectionInhabited(*hprop.readTy, *tprop.readTy);
+
+                            seenSet.erase(*hprop.readTy);
+                            seenSet.erase(*tprop.readTy);
+
+                            if (NormalizationResult::True != res)
+                                return {builtinTypes->neverType};
+
+                            TypeId ty = simplifyIntersection(builtinTypes, NotNull{arena}, *hprop.readTy, *tprop.readTy).result;
+                            prop.readTy = ty;
+                            hereSubThere &= (ty == hprop.readTy);
+                            thereSubHere &= (ty == tprop.readTy);
+                        }
                    }
                    else
                    {
@ -3055,12 +3040,15 @@ NormalizationResult Normalizer::intersectTyvarsWithTy(
    return NormalizationResult::True;
 }

-// See above for an explanation of `ignoreSmallerTyvars`.
+// See above for an explaination of `ignoreSmallerTyvars`.
 NormalizationResult Normalizer::intersectNormals(NormalizedType& here, const NormalizedType& there, int ignoreSmallerTyvars)
 {
-    RecursionCounter _rc(&sharedState->counters.recursionCount);
-    if (!withinResourceLimits())
-        return NormalizationResult::HitLimits;
+    if (FFlag::LuauIntersectNormalsNeedsToTrackResourceLimits)
+    {
+        RecursionCounter _rc(&sharedState->counters.recursionCount);
+        if (!withinResourceLimits())
+            return NormalizationResult::HitLimits;
+    }

    if (!get<NeverType>(there.tops))
    {
@ -3073,17 +3061,14 @@ NormalizationResult Normalizer::intersectNormals(NormalizedType& here, const Nor
        return unionNormals(here, there, ignoreSmallerTyvars);
    }

-    // Limit based on worst-case expansion of the table/function intersections
+    // Limit based on worst-case expansion of the table intersection
    // This restriction can be relaxed when table intersection simplification is improved
    if (here.tables.size() * there.tables.size() >= size_t(FInt::LuauNormalizeIntersectionLimit))
        return NormalizationResult::HitLimits;

-    if (here.functions.parts.size() * there.functions.parts.size() >= size_t(FInt::LuauNormalizeIntersectionLimit))
-        return NormalizationResult::HitLimits;
-
    here.booleans = intersectionOfBools(here.booleans, there.booleans);

-    intersectExternTypes(here.externTypes, there.externTypes);
+    intersectClasses(here.classes, there.classes);
    here.errors = (get<NeverType>(there.errors) ? there.errors : here.errors);
    here.nils = (get<NeverType>(there.nils) ? there.nils : here.nils);
    here.numbers = (get<NeverType>(there.numbers) ? there.numbers : here.numbers);
@ -3205,18 +3190,18 @@ NormalizationResult Normalizer::intersectNormalWithTy(
        intersectTablesWithTable(tables, there, seenTablePropPairs, seenSetTypes);
        here.tables = std::move(tables);
    }
-    else if (get<ExternType>(there))
+    else if (get<ClassType>(there))
    {
-        NormalizedExternType nct = std::move(here.externTypes);
+        NormalizedClassType nct = std::move(here.classes);
        clearNormal(here);
-        intersectExternTypesWithExternType(nct, there);
-        here.externTypes = std::move(nct);
+        intersectClassesWithClass(nct, there);
+        here.classes = std::move(nct);
    }
    else if (get<ErrorType>(there))
    {
        TypeId errors = here.errors;
        clearNormal(here);
-        here.errors = get<ErrorType>(errors) ? errors : there;
+        here.errors = errors;
    }
    else if (const PrimitiveType* ptv = get<PrimitiveType>(there))
    {
@ -3274,7 +3259,7 @@ NormalizationResult Normalizer::intersectNormalWithTy(
            subtractPrimitive(here, ntv->ty);
        else if (const SingletonType* stv = get<SingletonType>(t))
            subtractSingleton(here, follow(ntv->ty));
-        else if (get<ExternType>(t))
+        else if (get<ClassType>(t))
        {
            NormalizationResult res = intersectNormalWithNegationTy(t, here);
            if (shouldEarlyExit(res))
@ -3313,18 +3298,8 @@ NormalizationResult Normalizer::intersectNormalWithTy(
            clearNormal(here);
            return NormalizationResult::True;
        }
-        else if (get<ErrorType>(t))
-        {
-            // ~error is still an error, so intersecting with the negation is the same as intersecting with a type
-            TypeId errors = here.errors;
-            clearNormal(here);
-            here.errors = get<ErrorType>(errors) ? errors : t;
-        }
        else if (auto nt = get<NegationType>(t))
-        {
-            here.tyvars = std::move(tyvars);
            return intersectNormalWithTy(here, nt->ty, seenTablePropPairs, seenSetTypes);
-        }
        else
        {
            // TODO negated unions, intersections, table, and function.
@ -3334,7 +3309,7 @@ NormalizationResult Normalizer::intersectNormalWithTy(
    }
    else if (get<NeverType>(there))
    {
-        here.externTypes.resetToNever();
+        here.classes.resetToNever();
    }
    else if (get<NoRefineType>(there))
    {
@ -3352,43 +3327,19 @@ NormalizationResult Normalizer::intersectNormalWithTy(
    return NormalizationResult::True;
 }

-void makeTableShared_DEPRECATED(TypeId ty)
-{
-    ty = follow(ty);
-    if (auto tableTy = getMutable<TableType>(ty))
-    {
-        for (auto& [_, prop] : tableTy->props)
-            prop.makeShared();
-    }
-    else if (auto metatableTy = get<MetatableType>(ty))
-    {
-        makeTableShared_DEPRECATED(metatableTy->metatable);
-        makeTableShared_DEPRECATED(metatableTy->table);
-    }
-}
-
-void makeTableShared(TypeId ty, DenseHashSet<TypeId>& seen)
-{
-    ty = follow(ty);
-    if (seen.contains(ty))
-        return;
-    seen.insert(ty);
-    if (auto tableTy = getMutable<TableType>(ty))
-    {
-        for (auto& [_, prop] : tableTy->props)
-            prop.makeShared();
-    }
-    else if (auto metatableTy = get<MetatableType>(ty))
-    {
-        makeTableShared(metatableTy->metatable, seen);
-        makeTableShared(metatableTy->table, seen);
-    }
-}
-
 void makeTableShared(TypeId ty)
 {
-    DenseHashSet<TypeId> seen{nullptr};
-    makeTableShared(ty, seen);
+    ty = follow(ty);
+    if (auto tableTy = getMutable<TableType>(ty))
+    {
+        for (auto& [_, prop] : tableTy->props)
+            prop.makeShared();
+    }
+    else if (auto metatableTy = get<MetatableType>(ty))
+    {
+        makeTableShared(metatableTy->metatable);
+        makeTableShared(metatableTy->table);
+    }
 }

 // -------- Convert back from a normalized type to a type
@ -3403,18 +3354,18 @@ TypeId Normalizer::typeFromNormal(const NormalizedType& norm)
    if (!get<NeverType>(norm.booleans))
        result.push_back(norm.booleans);

-    if (isTop(builtinTypes, norm.externTypes))
+    if (isTop(builtinTypes, norm.classes))
    {
-        result.push_back(builtinTypes->externType);
+        result.push_back(builtinTypes->classType);
    }
-    else if (!norm.externTypes.isNever())
+    else if (!norm.classes.isNever())
    {
        std::vector<TypeId> parts;
-        parts.reserve(norm.externTypes.externTypes.size());
+        parts.reserve(norm.classes.classes.size());

-        for (const TypeId normTy : norm.externTypes.ordering)
+        for (const TypeId normTy : norm.classes.ordering)
        {
-            const TypeIds& normNegations = norm.externTypes.externTypes.at(normTy);
+            const TypeIds& normNegations = norm.classes.classes.at(normTy);

            if (normNegations.empty())
            {
@ -3490,10 +3441,7 @@ TypeId Normalizer::typeFromNormal(const NormalizedType& norm)
        result.reserve(result.size() + norm.tables.size());
        for (auto table : norm.tables)
        {
-            if (FFlag::LuauNormalizationCatchMetatableCycles)
-                makeTableShared(table);
-            else
-                makeTableShared_DEPRECATED(table);
+            makeTableShared(table);
            result.push_back(table);
        }
    }
--- a/Analysis/src/OverloadResolution.cpp
+++ b/Analysis/src/OverloadResolution.cpp
@ -10,8 +10,6 @@
 #include "Luau/TypeUtils.h"
 #include "Luau/Unifier2.h"

-LUAU_FASTFLAGVARIABLE(LuauArityMismatchOnUndersaturatedUnknownArguments)
-
 namespace Luau
 {

@ -256,32 +254,15 @@ std::pair<OverloadResolver::Analysis, ErrorVec> OverloadResolver::checkOverload_
            }

            // If any of the unsatisfied arguments are not supertypes of
-            // nil or are `unknown`, then this overload does not match.
+            // nil, then this overload does not match.
            for (size_t i = firstUnsatisfiedArgument; i < requiredHead.size(); ++i)
            {
-                if (FFlag::LuauArityMismatchOnUndersaturatedUnknownArguments)
+                if (!subtyping.isSubtype(builtinTypes->nilType, requiredHead[i], scope).isSubtype)
                {
-                    if (get<UnknownType>(follow(requiredHead[i])) || !subtyping.isSubtype(builtinTypes->nilType, requiredHead[i], scope).isSubtype)
-                    {
-                        auto [minParams, optMaxParams] = getParameterExtents(TxnLog::empty(), fn->argTypes);
-                        for (auto arg : fn->argTypes)
-                            if (get<UnknownType>(follow(arg)))
-                                minParams += 1;
+                    auto [minParams, optMaxParams] = getParameterExtents(TxnLog::empty(), fn->argTypes);
+                    TypeError error{fnExpr->location, CountMismatch{minParams, optMaxParams, args->head.size(), CountMismatch::Arg, isVariadic}};

-                        TypeError error{fnExpr->location, CountMismatch{minParams, optMaxParams, args->head.size(), CountMismatch::Arg, isVariadic}};
-
-                        return {Analysis::ArityMismatch, {error}};
-                    }
-                }
-                else
-                {
-                    if (!subtyping.isSubtype(builtinTypes->nilType, requiredHead[i], scope).isSubtype)
-                    {
-                        auto [minParams, optMaxParams] = getParameterExtents(TxnLog::empty(), fn->argTypes);
-                        TypeError error{fnExpr->location, CountMismatch{minParams, optMaxParams, args->head.size(), CountMismatch::Arg, isVariadic}};
-
-                        return {Analysis::ArityMismatch, {error}};
-                    }
+                    return {Analysis::ArityMismatch, {error}};
                }
            }

@ -473,7 +454,7 @@ SolveResult solveFunctionCall(

    TypePackId resultPack = arena->freshTypePack(scope);

-    TypeId inferredTy = arena->addType(FunctionType{TypeLevel{}, argsPack, resultPack});
+    TypeId inferredTy = arena->addType(FunctionType{TypeLevel{}, scope.get(), argsPack, resultPack});
    Unifier2 u2{NotNull{arena}, builtinTypes, scope, iceReporter};

    const bool occursCheckPassed = u2.unify(*overloadToUse, inferredTy);
--- a/Analysis/src/Quantify.cpp
+++ b/Analysis/src/Quantify.cpp
@ -107,4 +107,134 @@ void quantify(TypeId ty, TypeLevel level)
    ftv->genericPacks.insert(ftv->genericPacks.end(), q.genericPacks.begin(), q.genericPacks.end());
 }

+struct PureQuantifier : Substitution
+{
+    Scope* scope;
+    OrderedMap<TypeId, TypeId> insertedGenerics;
+    OrderedMap<TypePackId, TypePackId> insertedGenericPacks;
+    bool seenMutableType = false;
+    bool seenGenericType = false;
+
+    PureQuantifier(TypeArena* arena, Scope* scope)
+        : Substitution(TxnLog::empty(), arena)
+        , scope(scope)
+    {
+    }
+
+    bool isDirty(TypeId ty) override
+    {
+        LUAU_ASSERT(ty == follow(ty));
+
+        if (auto ftv = get<FreeType>(ty))
+        {
+            bool result = subsumes(scope, ftv->scope);
+            seenMutableType |= result;
+            return result;
+        }
+        else if (auto ttv = get<TableType>(ty))
+        {
+            if (ttv->state == TableState::Free)
+                seenMutableType = true;
+            else if (ttv->state == TableState::Generic)
+                seenGenericType = true;
+
+            return (ttv->state == TableState::Unsealed || ttv->state == TableState::Free) && subsumes(scope, ttv->scope);
+        }
+
+        return false;
+    }
+
+    bool isDirty(TypePackId tp) override
+    {
+        if (auto ftp = get<FreeTypePack>(tp))
+        {
+            return subsumes(scope, ftp->scope);
+        }
+
+        return false;
+    }
+
+    TypeId clean(TypeId ty) override
+    {
+        if (auto ftv = get<FreeType>(ty))
+        {
+            TypeId result = arena->addType(GenericType{scope});
+            insertedGenerics.push(ty, result);
+            return result;
+        }
+        else if (auto ttv = get<TableType>(ty))
+        {
+            TypeId result = arena->addType(TableType{});
+            TableType* resultTable = getMutable<TableType>(result);
+            LUAU_ASSERT(resultTable);
+
+            *resultTable = *ttv;
+            resultTable->level = TypeLevel{};
+            resultTable->scope = scope;
+
+            if (ttv->state == TableState::Free)
+            {
+                resultTable->state = TableState::Generic;
+                insertedGenerics.push(ty, result);
+            }
+            else if (ttv->state == TableState::Unsealed)
+                resultTable->state = TableState::Sealed;
+
+            return result;
+        }
+
+        return ty;
+    }
+
+    TypePackId clean(TypePackId tp) override
+    {
+        if (auto ftp = get<FreeTypePack>(tp))
+        {
+            TypePackId result = arena->addTypePack(TypePackVar{GenericTypePack{scope}});
+            insertedGenericPacks.push(tp, result);
+            return result;
+        }
+
+        return tp;
+    }
+
+    bool ignoreChildren(TypeId ty) override
+    {
+        if (get<ClassType>(ty))
+            return true;
+
+        return ty->persistent;
+    }
+    bool ignoreChildren(TypePackId ty) override
+    {
+        return ty->persistent;
+    }
+};
+
+std::optional<QuantifierResult> quantify(TypeArena* arena, TypeId ty, Scope* scope)
+{
+    PureQuantifier quantifier{arena, scope};
+    std::optional<TypeId> result = quantifier.substitute(ty);
+    if (!result)
+        return std::nullopt;
+
+    FunctionType* ftv = getMutable<FunctionType>(*result);
+    LUAU_ASSERT(ftv);
+    ftv->scope = scope;
+
+    for (auto k : quantifier.insertedGenerics.keys)
+    {
+        TypeId g = quantifier.insertedGenerics.pairings[k];
+        if (get<GenericType>(g))
+            ftv->generics.push_back(g);
+    }
+
+    for (auto k : quantifier.insertedGenericPacks.keys)
+        ftv->genericPacks.push_back(quantifier.insertedGenericPacks.pairings[k]);
+
+    ftv->hasNoFreeOrGenericTypes = ftv->generics.empty() && ftv->genericPacks.empty() && !quantifier.seenGenericType && !quantifier.seenMutableType;
+
+    return std::optional<QuantifierResult>({*result, std::move(quantifier.insertedGenerics), std::move(quantifier.insertedGenericPacks)});
+}
+
 } // namespace Luau
--- a/Analysis/src/Refinement.cpp
+++ b/Analysis/src/Refinement.cpp
@ -54,15 +54,7 @@ RefinementId RefinementArena::proposition(const RefinementKey* key, TypeId discr
    if (!key)
        return nullptr;

-    return NotNull{allocator.allocate(Proposition{key, discriminantTy, false})};
-}
-
-RefinementId RefinementArena::implicitProposition(const RefinementKey* key, TypeId discriminantTy)
-{
-    if (!key)
-        return nullptr;
-
-    return NotNull{allocator.allocate(Proposition{key, discriminantTy, true})};
+    return NotNull{allocator.allocate(Proposition{key, discriminantTy})};
 }

 } // namespace Luau
--- a/Analysis/src/RequireTracer.cpp
+++ b/Analysis/src/RequireTracer.cpp
@ -4,8 +4,6 @@
 #include "Luau/Ast.h"
 #include "Luau/Module.h"

-LUAU_FASTFLAG(LuauStoreReturnTypesAsPackOnAst)
-
 namespace Luau
 {

@ -67,13 +65,7 @@ struct RequireTracer : AstVisitor
        return true;
    }

-    bool visit(AstTypePack* node) override
-    {
-        // allow resolving require inside `typeof` annotations
-        return FFlag::LuauStoreReturnTypesAsPackOnAst;
-    }
-
-    AstExpr* getDependent_DEPRECATED(AstExpr* node)
+    AstExpr* getDependent(AstExpr* node)
    {
        if (AstExprLocal* expr = node->as<AstExprLocal>())
            return locals[expr->local];
@ -86,27 +78,6 @@ struct RequireTracer : AstVisitor
        else
            return nullptr;
    }
-    AstNode* getDependent(AstNode* node)
-    {
-        if (AstExprLocal* expr = node->as<AstExprLocal>())
-            return locals[expr->local];
-        else if (AstExprIndexName* expr = node->as<AstExprIndexName>())
-            return expr->expr;
-        else if (AstExprIndexExpr* expr = node->as<AstExprIndexExpr>())
-            return expr->expr;
-        else if (AstExprCall* expr = node->as<AstExprCall>(); expr && expr->self)
-            return expr->func->as<AstExprIndexName>()->expr;
-        else if (AstExprGroup* expr = node->as<AstExprGroup>())
-            return expr->expr;
-        else if (AstExprTypeAssertion* expr = node->as<AstExprTypeAssertion>())
-            return expr->annotation;
-        else if (AstTypeGroup* expr = node->as<AstTypeGroup>())
-            return expr->type;
-        else if (AstTypeTypeof* expr = node->as<AstTypeTypeof>())
-            return expr->expr;
-        else
-            return nullptr;
-    }

    void process()
    {
@ -120,15 +91,13 @@ struct RequireTracer : AstVisitor

        // push all dependent expressions to the work stack; note that the vector is modified during traversal
        for (size_t i = 0; i < work.size(); ++i)
-        {
-            if (AstNode* dep = getDependent(work[i]))
+            if (AstExpr* dep = getDependent(work[i]))
                work.push_back(dep);
-        }

        // resolve all expressions to a module info
        for (size_t i = work.size(); i > 0; --i)
        {
-            AstNode* expr = work[i - 1];
+            AstExpr* expr = work[i - 1];

            // when multiple expressions depend on the same one we push it to work queue multiple times
            if (result.exprs.contains(expr))
@ -136,22 +105,19 @@ struct RequireTracer : AstVisitor

            std::optional<ModuleInfo> info;

-            if (AstNode* dep = getDependent(expr))
+            if (AstExpr* dep = getDependent(expr))
            {
                const ModuleInfo* context = result.exprs.find(dep);

-                if (context && expr->is<AstExprLocal>())
-                    info = *context; // locals just inherit their dependent context, no resolution required
-                else if (context && (expr->is<AstExprGroup>() || expr->is<AstTypeGroup>()))
-                    info = *context; // simple group nodes propagate their value
-                else if (context && (expr->is<AstTypeTypeof>() || expr->is<AstExprTypeAssertion>()))
-                    info = *context; // typeof type annotations will resolve to the typeof content
-                else if (AstExpr* asExpr = expr->asExpr())
-                    info = fileResolver->resolveModule(context, asExpr);
+                // locals just inherit their dependent context, no resolution required
+                if (expr->is<AstExprLocal>())
+                    info = context ? std::optional<ModuleInfo>(*context) : std::nullopt;
+                else
+                    info = fileResolver->resolveModule(context, expr);
            }
-            else if (AstExpr* asExpr = expr->asExpr())
+            else
            {
-                info = fileResolver->resolveModule(&moduleContext, asExpr);
+                info = fileResolver->resolveModule(&moduleContext, expr);
            }

            if (info)
@ -184,7 +150,7 @@ struct RequireTracer : AstVisitor
    ModuleName currentModuleName;

    DenseHashMap<AstLocal*, AstExpr*> locals;
-    std::vector<AstNode*> work;
+    std::vector<AstExpr*> work;
    std::vector<AstExprCall*> requireCalls;
 };

--- a/Analysis/src/Scope.cpp
+++ b/Analysis/src/Scope.cpp
@ -84,17 +84,6 @@ std::optional<TypeId> Scope::lookupUnrefinedType(DefId def) const
    return std::nullopt;
 }

-std::optional<TypeId> Scope::lookupRValueRefinementType(DefId def) const
-{
-    for (const Scope* current = this; current; current = current->parent.get())
-    {
-        if (auto ty = current->rvalueRefinements.find(def))
-            return *ty;
-    }
-
-    return std::nullopt;
-}
-
 std::optional<TypeId> Scope::lookup(DefId def) const
 {
    for (const Scope* current = this; current; current = current->parent.get())
@ -192,29 +181,6 @@ std::optional<Binding> Scope::linearSearchForBinding(const std::string& name, bo
    return std::nullopt;
 }

-std::optional<std::pair<Symbol, Binding>> Scope::linearSearchForBindingPair(const std::string& name, bool traverseScopeChain) const
-{
-    const Scope* scope = this;
-
-    while (scope)
-    {
-        for (auto& [n, binding] : scope->bindings)
-        {
-            if (n.local && n.local->name == name.c_str())
-                return {{n, binding}};
-            else if (n.global.value && n.global == name.c_str())
-                return {{n, binding}};
-        }
-
-        scope = scope->parent.get();
-
-        if (!traverseScopeChain)
-            break;
-    }
-
-    return std::nullopt;
-}
-
 // Updates the `this` scope with the assignments from the `childScope` including ones that doesn't exist in `this`.
 void Scope::inheritAssignments(const ScopePtr& childScope)
 {
--- a/Analysis/src/Simplify.cpp
+++ b/Analysis/src/Simplify.cpp
@ -6,7 +6,6 @@
 #include "Luau/DenseHash.h"
 #include "Luau/RecursionCounter.h"
 #include "Luau/Set.h"
-#include "Luau/Type.h"
 #include "Luau/TypeArena.h"
 #include "Luau/TypePairHash.h"
 #include "Luau/TypeUtils.h"
@ -15,10 +14,8 @@

 LUAU_FASTINT(LuauTypeReductionRecursionLimit)
 LUAU_FASTFLAG(LuauSolverV2)
-LUAU_DYNAMIC_FASTINTVARIABLE(LuauSimplificationComplexityLimit, 8)
-LUAU_FASTFLAGVARIABLE(LuauSimplificationRecheckAssumption)
-LUAU_FASTFLAGVARIABLE(LuauOptimizeFalsyAndTruthyIntersect)
-LUAU_FASTFLAGVARIABLE(LuauSimplificationTableExternType)
+LUAU_DYNAMIC_FASTINTVARIABLE(LuauSimplificationComplexityLimit, 8);
+LUAU_FASTFLAGVARIABLE(LuauFlagBasicIntersectFollows);

 namespace Luau
 {
@ -34,27 +31,25 @@ struct TypeSimplifier

    int recursionDepth = 0;

-    TypeId mkNegation(TypeId ty) const;
+    TypeId mkNegation(TypeId ty);

    TypeId intersectFromParts(std::set<TypeId> parts);

-    TypeId intersectUnionWithType(TypeId left, TypeId right);
+    TypeId intersectUnionWithType(TypeId unionTy, TypeId right);
    TypeId intersectUnions(TypeId left, TypeId right);
-    TypeId intersectNegatedUnion(TypeId left, TypeId right);
+    TypeId intersectNegatedUnion(TypeId unionTy, TypeId right);

-    TypeId intersectTypeWithNegation(TypeId left, TypeId right);
-    TypeId intersectNegations(TypeId left, TypeId right);
+    TypeId intersectTypeWithNegation(TypeId a, TypeId b);
+    TypeId intersectNegations(TypeId a, TypeId b);

    TypeId intersectIntersectionWithType(TypeId left, TypeId right);

    // Attempt to intersect the two types.  Does not recurse.  Does not handle
    // unions, intersections, or negations.
    std::optional<TypeId> basicIntersect(TypeId left, TypeId right);
-    std::optional<TypeId> basicIntersectWithTruthy(TypeId target) const;
-    std::optional<TypeId> basicIntersectWithFalsy(TypeId target) const;

-    TypeId intersect(TypeId left, TypeId right);
-    TypeId union_(TypeId left, TypeId right);
+    TypeId intersect(TypeId ty, TypeId discriminant);
+    TypeId union_(TypeId ty, TypeId discriminant);

    TypeId simplify(TypeId ty);
    TypeId simplify(TypeId ty, DenseHashSet<TypeId>& seen);
@ -318,14 +313,12 @@ Relation relate(TypeId left, TypeId right, SimplifierSeenSet& seen)
    {
        if (get<AnyType>(right))
            return Relation::Subset;
-
-        if (get<UnknownType>(right))
+        else if (get<UnknownType>(right))
            return Relation::Coincident;
-
-        if (get<ErrorType>(right))
+        else if (get<ErrorType>(right))
            return Relation::Disjoint;
-
-        return Relation::Superset;
+        else
+            return Relation::Superset;
    }

    if (get<UnknownType>(right))
@ -335,8 +328,8 @@ Relation relate(TypeId left, TypeId right, SimplifierSeenSet& seen)
    {
        if (get<AnyType>(right))
            return Relation::Coincident;
-
-        return Relation::Superset;
+        else
+            return Relation::Superset;
    }

    if (get<AnyType>(right))
@ -360,7 +353,7 @@ Relation relate(TypeId left, TypeId right, SimplifierSeenSet& seen)
    // * FunctionType
    // * TableType
    // * MetatableType
-    // * ExternType
+    // * ClassType
    // * UnionType
    // * IntersectionType
    // * NegationType
@ -368,33 +361,26 @@ Relation relate(TypeId left, TypeId right, SimplifierSeenSet& seen)
    if (isTypeVariable(left) || isTypeVariable(right))
        return Relation::Intersects;

-    if (FFlag::LuauSimplificationTableExternType)
-    {
-        // if either type is a type function, we cannot know if they'll be related.
-        if (get<TypeFunctionInstanceType>(left) || get<TypeFunctionInstanceType>(right))
-            return Relation::Intersects;
-    }
-
    if (get<ErrorType>(left))
    {
        if (get<ErrorType>(right))
            return Relation::Coincident;
        else if (get<AnyType>(right))
            return Relation::Subset;
-
-        return Relation::Disjoint;
+        else
+            return Relation::Disjoint;
    }
-    else if (get<ErrorType>(right))
+    if (get<ErrorType>(right))
        return flip(relate(right, left, seen));

    if (get<NeverType>(left))
    {
        if (get<NeverType>(right))
            return Relation::Coincident;
-
-        return Relation::Subset;
+        else
+            return Relation::Subset;
    }
-    else if (get<NeverType>(right))
+    if (get<NeverType>(right))
        return flip(relate(right, left, seen));

    if (auto ut = get<IntersectionType>(left))
@ -458,54 +444,52 @@ Relation relate(TypeId left, TypeId right, SimplifierSeenSet& seen)
        {
            if (lp->type == rp->type)
                return Relation::Coincident;
-
-            return Relation::Disjoint;
+            else
+                return Relation::Disjoint;
        }

        if (auto rs = get<SingletonType>(right))
        {
            if (lp->type == PrimitiveType::String && rs->variant.get_if<StringSingleton>())
                return Relation::Superset;
-
-            if (lp->type == PrimitiveType::Boolean && rs->variant.get_if<BooleanSingleton>())
+            else if (lp->type == PrimitiveType::Boolean && rs->variant.get_if<BooleanSingleton>())
                return Relation::Superset;
-
-            return Relation::Disjoint;
+            else
+                return Relation::Disjoint;
        }

        if (lp->type == PrimitiveType::Function)
        {
            if (get<FunctionType>(right))
                return Relation::Superset;
-
-            return Relation::Disjoint;
+            else
+                return Relation::Disjoint;
        }
        if (lp->type == PrimitiveType::Table)
        {
            if (get<TableType>(right))
                return Relation::Superset;
-
-            return Relation::Disjoint;
+            else
+                return Relation::Disjoint;
        }

-        if (get<FunctionType>(right) || get<TableType>(right) || get<MetatableType>(right) || get<ExternType>(right))
+        if (get<FunctionType>(right) || get<TableType>(right) || get<MetatableType>(right) || get<ClassType>(right))
            return Relation::Disjoint;
    }

    if (auto ls = get<SingletonType>(left))
    {
-        if (get<FunctionType>(right) || get<TableType>(right) || get<MetatableType>(right) || get<ExternType>(right))
+        if (get<FunctionType>(right) || get<TableType>(right) || get<MetatableType>(right) || get<ClassType>(right))
            return Relation::Disjoint;

        if (get<PrimitiveType>(right))
            return flip(relate(right, left, seen));
-
        if (auto rs = get<SingletonType>(right))
        {
            if (ls->variant == rs->variant)
                return Relation::Coincident;
-
-            return Relation::Disjoint;
+            else
+                return Relation::Disjoint;
        }
    }

@ -515,11 +499,11 @@ Relation relate(TypeId left, TypeId right, SimplifierSeenSet& seen)
        {
            if (rp->type == PrimitiveType::Function)
                return Relation::Subset;
-
-            return Relation::Disjoint;
+            else
+                return Relation::Disjoint;
        }
-
-        return Relation::Intersects;
+        else
+            return Relation::Intersects;
    }

    if (auto lt = get<TableType>(left))
@ -528,11 +512,10 @@ Relation relate(TypeId left, TypeId right, SimplifierSeenSet& seen)
        {
            if (rp->type == PrimitiveType::Table)
                return Relation::Subset;
-
-            return Relation::Disjoint;
+            else
+                return Relation::Disjoint;
        }
-
-        if (auto rt = get<TableType>(right))
+        else if (auto rt = get<TableType>(right))
        {
            // TODO PROBABLY indexers and metatables.
            if (1 == rt->props.size())
@ -552,58 +535,29 @@ Relation relate(TypeId left, TypeId right, SimplifierSeenSet& seen)
                 */
                if (lt->props.size() > 1 && r == Relation::Superset)
                    return Relation::Intersects;
-
-                return r;
+                else
+                    return r;
            }
-
-            if (1 == lt->props.size())
+            else if (1 == lt->props.size())
                return flip(relate(right, left, seen));
-
-            return Relation::Intersects;
+            else
+                return Relation::Intersects;
        }
-
-        if (FFlag::LuauSimplificationTableExternType)
-        {
-            if (auto re = get<ExternType>(right))
-            {
-                Relation overall = Relation::Coincident;
-
-                for (auto& [name, prop] : lt->props)
-                {
-                    if (auto propInExternType = re->props.find(name); propInExternType != re->props.end())
-                    {
-                        Relation propRel = relate(prop.type(), propInExternType->second.type());
-
-                        if (propRel == Relation::Disjoint)
-                            return Relation::Disjoint;
-
-                        if (propRel == Relation::Coincident)
-                            continue;
-
-                        overall = Relation::Intersects;
-                    }
-                }
-
-                return overall;
-            }
-        }
-
        // TODO metatables

        return Relation::Disjoint;
    }

-    if (auto ct = get<ExternType>(left))
+    if (auto ct = get<ClassType>(left))
    {
-        if (auto rct = get<ExternType>(right))
+        if (auto rct = get<ClassType>(right))
        {
            if (isSubclass(ct, rct))
                return Relation::Subset;
-
-            if (isSubclass(rct, ct))
+            else if (isSubclass(rct, ct))
                return Relation::Superset;
-
-            return Relation::Disjoint;
+            else
+                return Relation::Disjoint;
        }

        return Relation::Disjoint;
@ -619,7 +573,7 @@ Relation relate(TypeId left, TypeId right)
    return relate(left, right, seen);
 }

-TypeId TypeSimplifier::mkNegation(TypeId ty) const
+TypeId TypeSimplifier::mkNegation(TypeId ty)
 {
    TypeId result = nullptr;

@ -753,9 +707,7 @@ TypeId TypeSimplifier::intersectUnionWithType(TypeId left, TypeId right)
    bool changed = false;
    std::set<TypeId> newParts;

-    size_t maxSize = DFInt::LuauSimplificationComplexityLimit;
-
-    if (leftUnion->options.size() > maxSize)
+    if (leftUnion->options.size() > (size_t)DFInt::LuauSimplificationComplexityLimit)
        return arena->addType(IntersectionType{{left, right}});

    for (TypeId part : leftUnion)
@ -770,13 +722,6 @@ TypeId TypeSimplifier::intersectUnionWithType(TypeId left, TypeId right)
        }

        newParts.insert(simplified);
-
-        if (FFlag::LuauSimplificationRecheckAssumption)
-        {
-            // Initial combination size check could not predict nested union iteration
-            if (newParts.size() > maxSize)
-                return arena->addType(IntersectionType{{left, right}});
-        }
    }

    if (!changed)
@ -817,13 +762,6 @@ TypeId TypeSimplifier::intersectUnions(TypeId left, TypeId right)
                continue;

            newParts.insert(simplified);
-
-            if (FFlag::LuauSimplificationRecheckAssumption)
-            {
-                // Initial combination size check could not predict nested union iteration
-                if (newParts.size() > maxSize)
-                    return arena->addType(IntersectionType{{left, right}});
-            }
        }
    }

@ -902,78 +840,6 @@ TypeId TypeSimplifier::intersectNegatedUnion(TypeId left, TypeId right)
        return intersectFromParts(std::move(newParts));
 }

-std::optional<TypeId> TypeSimplifier::basicIntersectWithTruthy(TypeId target) const
-{
-    target = follow(target);
-
-    if (is<UnknownType>(target))
-        return builtinTypes->truthyType;
-
-    if (is<AnyType>(target))
-        // any = *error-type* | unknown, so truthy & any = *error-type* | truthy
-        return arena->addType(UnionType{{builtinTypes->truthyType, builtinTypes->errorType}});
-
-    if (is<NeverType, ErrorType>(target))
-        return target;
-
-    if (is<FunctionType, TableType, MetatableType, ExternType>(target))
-        return target;
-
-    if (auto pt = get<PrimitiveType>(target))
-    {
-        switch (pt->type)
-        {
-        case PrimitiveType::NilType:
-            return builtinTypes->neverType;
-        case PrimitiveType::Boolean:
-            return builtinTypes->trueType;
-        default:
-            return target;
-        }
-    }
-
-    if (auto st = get<SingletonType>(target))
-        return st->variant == BooleanSingleton{false} ? builtinTypes->neverType : target;
-
-    return std::nullopt;
-}
-
-std::optional<TypeId> TypeSimplifier::basicIntersectWithFalsy(TypeId target) const
-{
-    target = follow(target);
-
-    if (is<NeverType, ErrorType>(target))
-        return target;
-
-    if (is<AnyType>(target))
-        // any = *error-type* | unknown, so falsy & any = *error-type* | falsy
-        return arena->addType(UnionType{{builtinTypes->falsyType, builtinTypes->errorType}});
-
-    if (is<UnknownType>(target))
-        return builtinTypes->falsyType;
-
-    if (is<FunctionType, TableType, MetatableType, ExternType>(target))
-        return builtinTypes->neverType;
-
-    if (auto pt = get<PrimitiveType>(target))
-    {
-        switch (pt->type)
-        {
-        case PrimitiveType::NilType:
-            return builtinTypes->nilType;
-        case PrimitiveType::Boolean:
-            return builtinTypes->falseType;
-        default:
-            return builtinTypes->neverType;
-        }
-    }
-
-    if (auto st = get<SingletonType>(target))
-        return st->variant == BooleanSingleton{false} ? builtinTypes->falseType : builtinTypes->neverType;
-
-    return std::nullopt;
-}
-
 TypeId TypeSimplifier::intersectTypeWithNegation(TypeId left, TypeId right)
 {
    const NegationType* leftNegation = get<NegationType>(left);
@ -1200,8 +1066,11 @@ TypeId TypeSimplifier::intersectIntersectionWithType(TypeId left, TypeId right)

 std::optional<TypeId> TypeSimplifier::basicIntersect(TypeId left, TypeId right)
 {
-    left = follow(left);
-    right = follow(right);
+    if (FFlag::LuauFlagBasicIntersectFollows)
+    {
+        left = follow(left);
+        right = follow(right);
+    }

    if (get<AnyType>(left) && get<ErrorType>(right))
        return right;
@ -1310,25 +1179,6 @@ std::optional<TypeId> TypeSimplifier::basicIntersect(TypeId left, TypeId right)
        return std::nullopt;
    }

-    if (FFlag::LuauOptimizeFalsyAndTruthyIntersect)
-    {
-        if (isTruthyType(left))
-            if (auto res = basicIntersectWithTruthy(right))
-                return res;
-
-        if (isTruthyType(right))
-            if (auto res = basicIntersectWithTruthy(left))
-                return res;
-
-        if (isFalsyType(left))
-            if (auto res = basicIntersectWithFalsy(right))
-                return res;
-
-        if (isFalsyType(right))
-            if (auto res = basicIntersectWithFalsy(left))
-                return res;
-    }
-
    Relation relation = relate(left, right);
    if (left == right || Relation::Coincident == relation)
        return left;
--- a/Analysis/src/Substitution.cpp
+++ b/Analysis/src/Substitution.cpp
@ -2,23 +2,24 @@
 #include "Luau/Substitution.h"

 #include "Luau/Common.h"
+#include "Luau/Clone.h"
 #include "Luau/TxnLog.h"
 #include "Luau/Type.h"

 #include <algorithm>
+#include <stdexcept>

 LUAU_FASTINTVARIABLE(LuauTarjanChildLimit, 10000)
 LUAU_FASTFLAG(LuauSolverV2)
 LUAU_FASTINTVARIABLE(LuauTarjanPreallocationSize, 256)
 LUAU_FASTFLAG(LuauSyntheticErrors)
-LUAU_FASTFLAG(LuauDeprecatedAttribute)

 namespace Luau
 {

-static TypeId shallowClone(TypeId ty, TypeArena& dest, const TxnLog* log)
+static TypeId shallowClone(TypeId ty, TypeArena& dest, const TxnLog* log, bool alwaysClone)
 {
-    auto go = [ty, &dest](auto&& a)
+    auto go = [ty, &dest, alwaysClone](auto&& a)
    {
        using T = std::decay_t<decltype(a)>;

@ -94,15 +95,13 @@ static TypeId shallowClone(TypeId ty, TypeArena& dest, const TxnLog* log)
            return dest.addType(a);
        else if constexpr (std::is_same_v<T, FunctionType>)
        {
-            FunctionType clone = FunctionType{a.level, a.argTypes, a.retTypes, a.definition, a.hasSelf};
+            FunctionType clone = FunctionType{a.level, a.scope, a.argTypes, a.retTypes, a.definition, a.hasSelf};
            clone.generics = a.generics;
            clone.genericPacks = a.genericPacks;
            clone.magic = a.magic;
            clone.tags = a.tags;
            clone.argNames = a.argNames;
            clone.isCheckedFunction = a.isCheckedFunction;
-            if (FFlag::LuauDeprecatedAttribute)
-                clone.isDeprecatedFunction = a.isDeprecatedFunction;
            return dest.addType(std::move(clone));
        }
        else if constexpr (std::is_same_v<T, TableType>)
@ -136,10 +135,15 @@ static TypeId shallowClone(TypeId ty, TypeArena& dest, const TxnLog* log)
            clone.parts = a.parts;
            return dest.addType(std::move(clone));
        }
-        else if constexpr (std::is_same_v<T, ExternType>)
+        else if constexpr (std::is_same_v<T, ClassType>)
        {
-            ExternType clone{a.name, a.props, a.parent, a.metatable, a.tags, a.userData, a.definitionModuleName, a.definitionLocation, a.indexer};
-            return dest.addType(std::move(clone));
+            if (alwaysClone)
+            {
+                ClassType clone{a.name, a.props, a.parent, a.metatable, a.tags, a.userData, a.definitionModuleName, a.definitionLocation, a.indexer};
+                return dest.addType(std::move(clone));
+            }
+            else
+                return ty;
        }
        else if constexpr (std::is_same_v<T, NegationType>)
            return dest.addType(NegationType{a.ty});
@ -252,21 +256,21 @@ void Tarjan::visitChildren(TypeId ty, int index)
        for (TypePackId a : tfit->packArguments)
            visitChild(a);
    }
-    else if (const ExternType* etv = get<ExternType>(ty))
+    else if (const ClassType* ctv = get<ClassType>(ty))
    {
-        for (const auto& [name, prop] : etv->props)
+        for (const auto& [name, prop] : ctv->props)
            visitChild(prop.type());

-        if (etv->parent)
-            visitChild(*etv->parent);
+        if (ctv->parent)
+            visitChild(*ctv->parent);

-        if (etv->metatable)
-            visitChild(*etv->metatable);
+        if (ctv->metatable)
+            visitChild(*ctv->metatable);

-        if (etv->indexer)
+        if (ctv->indexer)
        {
-            visitChild(etv->indexer->indexType);
-            visitChild(etv->indexer->indexResultType);
+            visitChild(ctv->indexer->indexType);
+            visitChild(ctv->indexer->indexResultType);
        }
    }
    else if (const NegationType* ntv = get<NegationType>(ty))
@ -540,27 +544,6 @@ void Tarjan::visitSCC(int index)
    }
 }

-bool Tarjan::ignoreChildren(TypeId ty)
-{
-    return false;
-}
-
-bool Tarjan::ignoreChildren(TypePackId ty)
-{
-    return false;
-}
-
-// Some subclasses might ignore children visit, but not other actions like replacing the children
-bool Tarjan::ignoreChildrenVisit(TypeId ty)
-{
-    return ignoreChildren(ty);
-}
-
-bool Tarjan::ignoreChildrenVisit(TypePackId ty)
-{
-    return ignoreChildren(ty);
-}
-
 TarjanResult Tarjan::findDirty(TypeId ty)
 {
    return visitRoot(ty);
@ -571,11 +554,6 @@ TarjanResult Tarjan::findDirty(TypePackId tp)
    return visitRoot(tp);
 }

-Substitution::Substitution(TypeArena* arena)
-    : Substitution(TxnLog::empty(), arena)
-{
-}
-
 Substitution::Substitution(const TxnLog* log_, TypeArena* arena)
    : arena(arena)
 {
@ -676,7 +654,7 @@ void Substitution::resetState(const TxnLog* log, TypeArena* arena)

 TypeId Substitution::clone(TypeId ty)
 {
-    return shallowClone(ty, *arena, log);
+    return shallowClone(ty, *arena, log, /* alwaysClone */ true);
 }

 TypePackId Substitution::clone(TypePackId tp)
@ -838,21 +816,21 @@ void Substitution::replaceChildren(TypeId ty)
        for (TypePackId& a : tfit->packArguments)
            a = replace(a);
    }
-    else if (ExternType* etv = getMutable<ExternType>(ty))
+    else if (ClassType* ctv = getMutable<ClassType>(ty))
    {
-        for (auto& [name, prop] : etv->props)
+        for (auto& [name, prop] : ctv->props)
            prop.setType(replace(prop.type()));

-        if (etv->parent)
-            etv->parent = replace(*etv->parent);
+        if (ctv->parent)
+            ctv->parent = replace(*ctv->parent);

-        if (etv->metatable)
-            etv->metatable = replace(*etv->metatable);
+        if (ctv->metatable)
+            ctv->metatable = replace(*ctv->metatable);

-        if (etv->indexer)
+        if (ctv->indexer)
        {
-            etv->indexer->indexType = replace(etv->indexer->indexType);
-            etv->indexer->indexResultType = replace(etv->indexer->indexResultType);
+            ctv->indexer->indexType = replace(ctv->indexer->indexType);
+            ctv->indexer->indexResultType = replace(ctv->indexer->indexResultType);
        }
    }
    else if (NegationType* ntv = getMutable<NegationType>(ty))
@ -892,13 +870,4 @@ void Substitution::replaceChildren(TypePackId tp)
    }
 }

-template<typename Ty>
-std::optional<Ty> Substitution::replace(std::optional<Ty> ty)
-{
-    if (ty)
-        return replace(*ty);
-    else
-        return std::nullopt;
-}
-
 } // namespace Luau
--- a/Analysis/src/Subtyping.cpp
+++ b/Analysis/src/Subtyping.cpp
@ -7,11 +7,13 @@
 #include "Luau/Normalize.h"
 #include "Luau/RecursionCounter.h"
 #include "Luau/Scope.h"
+#include "Luau/StringUtils.h"
 #include "Luau/Substitution.h"
 #include "Luau/ToString.h"
 #include "Luau/TxnLog.h"
 #include "Luau/Type.h"
 #include "Luau/TypeArena.h"
+#include "Luau/TypeCheckLimits.h"
 #include "Luau/TypeFunction.h"
 #include "Luau/TypePack.h"
 #include "Luau/TypePath.h"
@ -20,8 +22,7 @@
 #include <algorithm>

 LUAU_FASTFLAGVARIABLE(DebugLuauSubtypingCheckPathValidity)
-LUAU_FASTINTVARIABLE(LuauSubtypingReasoningLimit, 100)
-LUAU_FASTFLAGVARIABLE(LuauSubtypingEnableReasoningLimit)
+LUAU_FASTFLAGVARIABLE(LuauRetrySubtypingWithoutHiddenPack)

 namespace Luau
 {
@ -31,7 +32,7 @@ struct VarianceFlipper
    Subtyping::Variance* variance;
    Subtyping::Variance oldValue;

-    explicit VarianceFlipper(Subtyping::Variance* v)
+    VarianceFlipper(Subtyping::Variance* v)
        : variance(v)
        , oldValue(*v)
    {
@ -99,9 +100,6 @@ static SubtypingReasonings mergeReasonings(const SubtypingReasonings& a, const S
            else
                result.insert(r);
        }
-
-        if (FFlag::LuauSubtypingEnableReasoningLimit && result.size() >= size_t(FInt::LuauSubtypingReasoningLimit))
-            return result;
    }

    for (const SubtypingReasoning& r : b)
@ -118,9 +116,6 @@ static SubtypingReasonings mergeReasonings(const SubtypingReasonings& a, const S
            else
                result.insert(r);
        }
-
-        if (FFlag::LuauSubtypingEnableReasoningLimit && result.size() >= size_t(FInt::LuauSubtypingReasoningLimit))
-            return result;
    }

    return result;
@ -313,7 +308,7 @@ struct ApplyMappedGenerics : Substitution

    bool ignoreChildren(TypeId ty) override
    {
-        if (get<ExternType>(ty))
+        if (get<ClassType>(ty))
            return true;

        return ty->persistent;
@ -421,14 +416,6 @@ SubtypingResult Subtyping::isSubtype(TypeId subTy, TypeId superTy, NotNull<Scope

    SubtypingResult result = isCovariantWith(env, subTy, superTy, scope);

-    if (result.normalizationTooComplex)
-    {
-        if (result.isCacheable)
-            resultCache[{subTy, superTy}] = result;
-
-        return result;
-    }
-
    for (const auto& [subTy, bounds] : env.mappedGenerics)
    {
        const auto& lb = bounds.lowerBound;
@ -606,12 +593,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypeId sub
        if (!result.isSubtype && !result.normalizationTooComplex)
        {
            SubtypingResult semantic = isCovariantWith(env, normalizer->normalize(subTy), normalizer->normalize(superTy), scope);
-
-            if (semantic.normalizationTooComplex)
-            {
-                result = semantic;
-            }
-            else if (semantic.isSubtype)
+            if (semantic.isSubtype)
            {
                semantic.reasoning.clear();
                result = semantic;
@ -626,12 +608,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypeId sub
        if (!result.isSubtype && !result.normalizationTooComplex)
        {
            SubtypingResult semantic = isCovariantWith(env, normalizer->normalize(subTy), normalizer->normalize(superTy), scope);
-
-            if (semantic.normalizationTooComplex)
-            {
-                result = semantic;
-            }
-            else if (semantic.isSubtype)
+            if (semantic.isSubtype)
            {
                // Clear the semantic reasoning, as any reasonings within
                // potentially contain invalid paths.
@ -742,9 +719,9 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypeId sub
        result = isCovariantWith(env, p, scope);
    else if (auto p = get2<MetatableType, TableType>(subTy, superTy))
        result = isCovariantWith(env, p, scope);
-    else if (auto p = get2<ExternType, ExternType>(subTy, superTy))
+    else if (auto p = get2<ClassType, ClassType>(subTy, superTy))
        result = isCovariantWith(env, p, scope);
-    else if (auto p = get2<ExternType, TableType>(subTy, superTy))
+    else if (auto p = get2<ClassType, TableType>(subTy, superTy))
        result = isCovariantWith(env, subTy, p.first, superTy, p.second, scope);
    else if (auto p = get2<TableType, PrimitiveType>(subTy, superTy))
        result = isCovariantWith(env, p, scope);
@ -777,8 +754,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypePackId
    // Match head types pairwise

    for (size_t i = 0; i < headSize; ++i)
-        results.push_back(isCovariantWith(env, subHead[i], superHead[i], scope).withBothComponent(TypePath::Index{i, TypePath::Index::Variant::Pack})
-        );
+        results.push_back(isCovariantWith(env, subHead[i], superHead[i], scope).withBothComponent(TypePath::Index{i}));

    // Handle mismatched head sizes

@ -791,7 +767,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypePackId
                for (size_t i = headSize; i < superHead.size(); ++i)
                    results.push_back(isCovariantWith(env, vt->ty, superHead[i], scope)
                                          .withSubPath(TypePath::PathBuilder().tail().variadic().build())
-                                          .withSuperComponent(TypePath::Index{i, TypePath::Index::Variant::Pack}));
+                                          .withSuperComponent(TypePath::Index{i}));
            }
            else if (auto gt = get<GenericTypePack>(*subTail))
            {
@ -845,7 +821,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypePackId
            {
                for (size_t i = headSize; i < subHead.size(); ++i)
                    results.push_back(isCovariantWith(env, subHead[i], vt->ty, scope)
-                                          .withSubComponent(TypePath::Index{i, TypePath::Index::Variant::Pack})
+                                          .withSubComponent(TypePath::Index{i})
                                          .withSuperPath(TypePath::PathBuilder().tail().variadic().build()));
            }
            else if (auto gt = get<GenericTypePack>(*superTail))
@ -883,7 +859,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypePackId
            else
                return SubtypingResult{false}
                    .withSuperComponent(TypePath::PackField::Tail)
-                    .withError({scope->location, UnexpectedTypePackInSubtyping{*superTail}});
+                    .withError({scope->location, UnexpectedTypePackInSubtyping{*subTail}});
        }
        else
            return {false};
@ -1106,10 +1082,6 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypeId sub
    for (TypeId ty : superUnion)
    {
        SubtypingResult next = isCovariantWith(env, subTy, ty, scope);
-
-        if (next.normalizationTooComplex)
-            return SubtypingResult{false, /* normalizationTooComplex */ true};
-
        if (next.isSubtype)
            return SubtypingResult{true};
    }
@ -1128,13 +1100,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const Unio
    std::vector<SubtypingResult> subtypings;
    size_t i = 0;
    for (TypeId ty : subUnion)
-    {
-        subtypings.push_back(isCovariantWith(env, ty, superTy, scope).withSubComponent(TypePath::Index{i++, TypePath::Index::Variant::Union}));
-
-        if (subtypings.back().normalizationTooComplex)
-            return SubtypingResult{false, /* normalizationTooComplex */ true};
-    }
-
+        subtypings.push_back(isCovariantWith(env, ty, superTy, scope).withSubComponent(TypePath::Index{i++}));
    return SubtypingResult::all(subtypings);
 }

@ -1144,13 +1110,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, TypeId sub
    std::vector<SubtypingResult> subtypings;
    size_t i = 0;
    for (TypeId ty : superIntersection)
-    {
-        subtypings.push_back(isCovariantWith(env, subTy, ty, scope).withSuperComponent(TypePath::Index{i++, TypePath::Index::Variant::Intersection}));
-
-        if (subtypings.back().normalizationTooComplex)
-            return SubtypingResult{false, /* normalizationTooComplex */ true};
-    }
-
+        subtypings.push_back(isCovariantWith(env, subTy, ty, scope).withSuperComponent(TypePath::Index{i++}));
    return SubtypingResult::all(subtypings);
 }

@ -1160,13 +1120,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const Inte
    std::vector<SubtypingResult> subtypings;
    size_t i = 0;
    for (TypeId ty : subIntersection)
-    {
-        subtypings.push_back(isCovariantWith(env, ty, superTy, scope).withSubComponent(TypePath::Index{i++, TypePath::Index::Variant::Intersection}));
-
-        if (subtypings.back().normalizationTooComplex)
-            return SubtypingResult{false, /* normalizationTooComplex */ true};
-    }
-
+        subtypings.push_back(isCovariantWith(env, ty, superTy, scope).withSubComponent(TypePath::Index{i++}));
    return SubtypingResult::any(subtypings);
 }

@ -1334,7 +1288,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const Type
    }
    // the top class type is not actually a primitive type, so the negation of
    // any one of them includes the top class type.
-    else if (auto p = get2<ExternType, PrimitiveType>(subTy, negatedTy))
+    else if (auto p = get2<ClassType, PrimitiveType>(subTy, negatedTy))
        result = {true};
    else if (auto p = get<PrimitiveType>(negatedTy); p && is<TableType, MetatableType>(subTy))
        result = {p->type != PrimitiveType::Table};
@ -1342,9 +1296,9 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const Type
        result = {p.second->type != PrimitiveType::Function};
    else if (auto p = get2<SingletonType, SingletonType>(subTy, negatedTy))
        result = {*p.first != *p.second};
-    else if (auto p = get2<ExternType, ExternType>(subTy, negatedTy))
+    else if (auto p = get2<ClassType, ClassType>(subTy, negatedTy))
        result = SubtypingResult::negate(isCovariantWith(env, p.first, p.second, scope));
-    else if (get2<FunctionType, ExternType>(subTy, negatedTy))
+    else if (get2<FunctionType, ClassType>(subTy, negatedTy))
        result = {true};
    else if (is<ErrorType, FunctionType, TableType, MetatableType>(negatedTy))
        iceReporter->ice("attempting to negate a non-testable type");
@ -1456,7 +1410,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const Meta
        // of the supertype table.
        //
        // There's a flaw here in that if the __index metamethod contributes a new
-        // field that would satisfy the subtyping relationship, we'll erroneously say
+        // field that would satisfy the subtyping relationship, we'll erronously say
        // that the metatable isn't a subtype of the table, even though they have
        // compatible properties/shapes. We'll revisit this later when we have a
        // better understanding of how important this is.
@ -1469,15 +1423,15 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const Meta
    }
 }

-SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const ExternType* subExternType, const ExternType* superExternType, NotNull<Scope> scope)
+SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const ClassType* subClass, const ClassType* superClass, NotNull<Scope> scope)
 {
-    return {isSubclass(subExternType, superExternType)};
+    return {isSubclass(subClass, superClass)};
 }

 SubtypingResult Subtyping::isCovariantWith(
    SubtypingEnvironment& env,
    TypeId subTy,
-    const ExternType* subExternType,
+    const ClassType* subClass,
    TypeId superTy,
    const TableType* superTable,
    NotNull<Scope> scope
@ -1489,7 +1443,7 @@ SubtypingResult Subtyping::isCovariantWith(

    for (const auto& [name, prop] : superTable->props)
    {
-        if (auto classProp = lookupExternTypeProp(subExternType, name))
+        if (auto classProp = lookupClassProp(subClass, name))
        {
            result.andAlso(isCovariantWith(env, *classProp, prop, name, scope));
        }
@ -1520,7 +1474,7 @@ SubtypingResult Subtyping::isCovariantWith(

        // If subtyping failed in the argument packs, we should check if there's a hidden variadic tail and try ignoring it.
        // This might cause subtyping correctly because the sub type here may not have a hidden variadic tail or equivalent.
-        if (!result.isSubtype)
+        if (FFlag::LuauRetrySubtypingWithoutHiddenPack && !result.isSubtype)
        {
            auto [arguments, tail] = flatten(superFunction->argTypes);

@ -1659,7 +1613,7 @@ SubtypingResult Subtyping::isCovariantWith(
    SubtypingResult result = isCovariantWith(env, subNorm->tops, superNorm->tops, scope);
    result.andAlso(isCovariantWith(env, subNorm->booleans, superNorm->booleans, scope));
    result.andAlso(
-        isCovariantWith(env, subNorm->externTypes, superNorm->externTypes, scope).orElse(isCovariantWith(env, subNorm->externTypes, superNorm->tables, scope))
+        isCovariantWith(env, subNorm->classes, superNorm->classes, scope).orElse(isCovariantWith(env, subNorm->classes, superNorm->tables, scope))
    );
    result.andAlso(isCovariantWith(env, subNorm->errors, superNorm->errors, scope));
    result.andAlso(isCovariantWith(env, subNorm->nils, superNorm->nils, scope));
@ -1676,24 +1630,24 @@ SubtypingResult Subtyping::isCovariantWith(

 SubtypingResult Subtyping::isCovariantWith(
    SubtypingEnvironment& env,
-    const NormalizedExternType& subExternType,
-    const NormalizedExternType& superExternType,
+    const NormalizedClassType& subClass,
+    const NormalizedClassType& superClass,
    NotNull<Scope> scope
 )
 {
-    for (const auto& [subExternTypeTy, _] : subExternType.externTypes)
+    for (const auto& [subClassTy, _] : subClass.classes)
    {
        SubtypingResult result;

-        for (const auto& [superExternTypeTy, superNegations] : superExternType.externTypes)
+        for (const auto& [superClassTy, superNegations] : superClass.classes)
        {
-            result.orElse(isCovariantWith(env, subExternTypeTy, superExternTypeTy, scope));
+            result.orElse(isCovariantWith(env, subClassTy, superClassTy, scope));
            if (!result.isSubtype)
                continue;

            for (TypeId negation : superNegations)
            {
-                result.andAlso(SubtypingResult::negate(isCovariantWith(env, subExternTypeTy, negation, scope)));
+                result.andAlso(SubtypingResult::negate(isCovariantWith(env, subClassTy, negation, scope)));
                if (result.isSubtype)
                    break;
            }
@ -1708,17 +1662,17 @@ SubtypingResult Subtyping::isCovariantWith(

 SubtypingResult Subtyping::isCovariantWith(
    SubtypingEnvironment& env,
-    const NormalizedExternType& subExternType,
+    const NormalizedClassType& subClass,
    const TypeIds& superTables,
    NotNull<Scope> scope
 )
 {
-    for (const auto& [subExternTypeTy, _] : subExternType.externTypes)
+    for (const auto& [subClassTy, _] : subClass.classes)
    {
        SubtypingResult result;

        for (TypeId superTableTy : superTables)
-            result.orElse(isCovariantWith(env, subExternTypeTy, superTableTy, scope));
+            result.orElse(isCovariantWith(env, subClassTy, superTableTy, scope));

        if (!result.isSubtype)
            return result;
@ -1806,12 +1760,7 @@ SubtypingResult Subtyping::isCovariantWith(SubtypingEnvironment& env, const Type
    {
        results.emplace_back();
        for (TypeId superTy : superTypes)
-        {
            results.back().orElse(isCovariantWith(env, subTy, superTy, scope));
-
-            if (results.back().normalizationTooComplex)
-                return SubtypingResult{false, /* normalizationTooComplex */ true};
-        }
    }

    return SubtypingResult::all(results);
--- a/Analysis/src/Symbol.cpp
+++ b/Analysis/src/Symbol.cpp
@ -4,6 +4,7 @@
 #include "Luau/Common.h"

 LUAU_FASTFLAG(LuauSolverV2)
+LUAU_FASTFLAGVARIABLE(LuauSymbolEquality)

 namespace Luau
 {
@ -14,8 +15,10 @@ bool Symbol::operator==(const Symbol& rhs) const
        return local == rhs.local;
    else if (global.value)
        return rhs.global.value && global == rhs.global.value; // Subtlety: AstName::operator==(const char*) uses strcmp, not pointer identity.
-    else
+    else if (FFlag::LuauSolverV2 || FFlag::LuauSymbolEquality)
        return !rhs.local && !rhs.global.value; // Reflexivity: we already know `this` Symbol is empty, so check that rhs is.
+    else
+        return false;
 }

 std::string toString(const Symbol& name)
--- a/Analysis/src/TableLiteralInference.cpp
+++ b/Analysis/src/TableLiteralInference.cpp
@ -1,22 +1,14 @@
 // This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details

-#include "Luau/TableLiteralInference.h"
-
 #include "Luau/Ast.h"
-#include "Luau/Common.h"
 #include "Luau/Normalize.h"
 #include "Luau/Simplify.h"
-#include "Luau/Subtyping.h"
 #include "Luau/Type.h"
 #include "Luau/ToString.h"
 #include "Luau/TypeArena.h"
 #include "Luau/TypeUtils.h"
 #include "Luau/Unifier2.h"

-LUAU_FASTFLAGVARIABLE(LuauBidirectionalInferenceCollectIndexerTypes)
-LUAU_FASTFLAGVARIABLE(LuauBidirectionalFailsafe)
-LUAU_FASTFLAGVARIABLE(LuauBidirectionalInferenceElideAssert)
-
 namespace Luau
 {

@ -117,7 +109,6 @@ TypeId matchLiteralType(
    NotNull<BuiltinTypes> builtinTypes,
    NotNull<TypeArena> arena,
    NotNull<Unifier2> unifier,
-    NotNull<Subtyping> subtyping,
    TypeId expectedType,
    TypeId exprType,
    const AstExpr* expr,
@ -138,33 +129,17 @@ TypeId matchLiteralType(
     * things like replace explicit named properties with indexers as required
     * by the expected type.
     */
-
    if (!isLiteral(expr))
-    {
-        auto result = subtyping->isSubtype(/*subTy=*/exprType, /*superTy=*/expectedType, unifier->scope);
-        return result.isSubtype ? expectedType : exprType;
-    }
+        return exprType;

    expectedType = follow(expectedType);
    exprType = follow(exprType);

-    if (FFlag::LuauBidirectionalInferenceCollectIndexerTypes)
+    if (get<AnyType>(expectedType) || get<UnknownType>(expectedType))
    {
-        // The intent of `matchLiteralType` is to upcast values when it's safe
-        // to do so. it's always safe to upcast to `any` or `unknown`, so we
-        // can unconditionally do so here.
-        if (is<AnyType, UnknownType>(expectedType))
-            return expectedType;
+        // "Narrowing" to unknown or any is not going to do anything useful.
+        return exprType;
    }
-    else
-    {
-        if (get<AnyType>(expectedType) || get<UnknownType>(expectedType))
-        {
-            // "Narrowing" to unknown or any is not going to do anything useful.
-            return exprType;
-        }
-    }
-

    if (expr->is<AstExprConstantString>())
    {
@ -232,27 +207,11 @@ TypeId matchLiteralType(
        return exprType;
    }

-
-    if (expr->is<AstExprFunction>())
-    {
-        // TODO: Push argument / return types into the lambda. For now, just do
-        // the non-literal thing: check for a subtype and upcast if valid.
-        auto result = subtyping->isSubtype(/*subTy=*/exprType, /*superTy=*/expectedType, unifier->scope);
-        return result.isSubtype ? expectedType : exprType;
-    }
+    // TODO: lambdas

    if (auto exprTable = expr->as<AstExprTable>())
    {
        TableType* const tableTy = getMutable<TableType>(exprType);
-
-        // This can occur if we have an expression like:
-        //
-        //  { x = {}, x = 42 }
-        //
-        // The type of this will be `{ x: number }`
-        if (FFlag::LuauBidirectionalFailsafe && !tableTy)
-            return exprType;
-
        LUAU_ASSERT(tableTy);

        const TableType* expectedTableTy = get<TableType>(expectedType);
@ -267,7 +226,7 @@ TypeId matchLiteralType(

                if (tt)
                {
-                    TypeId res = matchLiteralType(astTypes, astExpectedTypes, builtinTypes, arena, unifier, subtyping, *tt, exprType, expr, toBlock);
+                    TypeId res = matchLiteralType(astTypes, astExpectedTypes, builtinTypes, arena, unifier, *tt, exprType, expr, toBlock);

                    parts.push_back(res);
                    return arena->addType(UnionType{std::move(parts)});
@ -277,11 +236,6 @@ TypeId matchLiteralType(
            return exprType;
        }

-        DenseHashSet<AstExprConstantString*> keysToDelete{nullptr};
-
-        DenseHashSet<TypeId> indexerKeyTypes{nullptr};
-        DenseHashSet<TypeId> indexerValueTypes{nullptr};
-
        for (const AstExprTable::Item& item : exprTable->items)
        {
            if (isRecord(item))
@ -289,20 +243,12 @@ TypeId matchLiteralType(
                const AstArray<char>& s = item.key->as<AstExprConstantString>()->value;
                std::string keyStr{s.data, s.data + s.size};
                auto it = tableTy->props.find(keyStr);
-
-                // This can occur, potentially, if we are re-entrant.
-                if (FFlag::LuauBidirectionalFailsafe && it == tableTy->props.end())
-                    continue;
-
                LUAU_ASSERT(it != tableTy->props.end());

                Property& prop = it->second;

-                // If we encounter a duplcate property, we may have already
-                // set it to be read-only. If that's the case, the only thing
-                // that will definitely crash is trying to access a write
-                // only property.
-                LUAU_ASSERT(!prop.isWriteOnly());
+                // Table literals always initially result in shared read-write types
+                LUAU_ASSERT(prop.isShared());
                TypeId propTy = *prop.readTy;

                auto it2 = expectedTableTy->props.find(keyStr);
@ -323,27 +269,18 @@ TypeId matchLiteralType(
                            builtinTypes,
                            arena,
                            unifier,
-                            subtyping,
                            expectedTableTy->indexer->indexResultType,
                            propTy,
                            item.value,
                            toBlock
                        );

-                        if (FFlag::LuauBidirectionalInferenceCollectIndexerTypes)
-                        {
-                            indexerKeyTypes.insert(arena->addType(SingletonType{StringSingleton{keyStr}}));
-                            indexerValueTypes.insert(matchedType);
-                        }
+                        if (tableTy->indexer)
+                            unifier->unify(matchedType, tableTy->indexer->indexResultType);
                        else
-                        {
-                            if (tableTy->indexer)
-                                unifier->unify(matchedType, tableTy->indexer->indexResultType);
-                            else
-                                tableTy->indexer = TableIndexer{expectedTableTy->indexer->indexType, matchedType};
-                        }
+                            tableTy->indexer = TableIndexer{expectedTableTy->indexer->indexType, matchedType};

-                        keysToDelete.insert(item.key->as<AstExprConstantString>());
+                        tableTy->props.erase(keyStr);
                    }

                    // If it's just an extra property and the expected type
@ -366,25 +303,22 @@ TypeId matchLiteralType(
                // quadratic in a hurry.
                if (expectedProp.isShared())
                {
-                    matchedType = matchLiteralType(
-                        astTypes, astExpectedTypes, builtinTypes, arena, unifier, subtyping, *expectedReadTy, propTy, item.value, toBlock
-                    );
+                    matchedType =
+                        matchLiteralType(astTypes, astExpectedTypes, builtinTypes, arena, unifier, *expectedReadTy, propTy, item.value, toBlock);
                    prop.readTy = matchedType;
                    prop.writeTy = matchedType;
                }
                else if (expectedReadTy)
                {
-                    matchedType = matchLiteralType(
-                        astTypes, astExpectedTypes, builtinTypes, arena, unifier, subtyping, *expectedReadTy, propTy, item.value, toBlock
-                    );
+                    matchedType =
+                        matchLiteralType(astTypes, astExpectedTypes, builtinTypes, arena, unifier, *expectedReadTy, propTy, item.value, toBlock);
                    prop.readTy = matchedType;
                    prop.writeTy.reset();
                }
                else if (expectedWriteTy)
                {
-                    matchedType = matchLiteralType(
-                        astTypes, astExpectedTypes, builtinTypes, arena, unifier, subtyping, *expectedWriteTy, propTy, item.value, toBlock
-                    );
+                    matchedType =
+                        matchLiteralType(astTypes, astExpectedTypes, builtinTypes, arena, unifier, *expectedWriteTy, propTy, item.value, toBlock);
                    prop.readTy.reset();
                    prop.writeTy = matchedType;
                }
@ -401,16 +335,10 @@ TypeId matchLiteralType(
                LUAU_ASSERT(matchedType);

                (*astExpectedTypes)[item.value] = matchedType;
-                // NOTE: We do *not* add to the potential indexer types here.
-                // I think this is correct to support something like:
-                //
-                //  { [string]: number, foo: boolean }
-                //
            }
            else if (item.kind == AstExprTable::Item::List)
            {
-                if (!FFlag::LuauBidirectionalInferenceCollectIndexerTypes || !FFlag::LuauBidirectionalInferenceElideAssert)
-                    LUAU_ASSERT(tableTy->indexer);
+                LUAU_ASSERT(tableTy->indexer);

                if (expectedTableTy->indexer)
                {
@ -424,24 +352,15 @@ TypeId matchLiteralType(
                        builtinTypes,
                        arena,
                        unifier,
-                        subtyping,
                        expectedTableTy->indexer->indexResultType,
                        *propTy,
                        item.value,
                        toBlock
                    );

-                    if (FFlag::LuauBidirectionalInferenceCollectIndexerTypes)
-                    {
-                        indexerKeyTypes.insert(builtinTypes->numberType);
-                        indexerValueTypes.insert(matchedType);
-                    }
-                    else
-                    {
-                        // if the index result type is the prop type, we can replace it with the matched type here.
-                        if (tableTy->indexer->indexResultType == *propTy)
-                            tableTy->indexer->indexResultType = matchedType;
-                    }
+                    // if the index result type is the prop type, we can replace it with the matched type here.
+                    if (tableTy->indexer->indexResultType == *propTy)
+                        tableTy->indexer->indexResultType = matchedType;
                }
            }
            else if (item.kind == AstExprTable::Item::General)
@ -463,24 +382,11 @@ TypeId matchLiteralType(
                // Populate expected types for non-string keys declared with [] (the code below will handle the case where they are strings)
                if (!item.key->as<AstExprConstantString>() && expectedTableTy->indexer)
                    (*astExpectedTypes)[item.key] = expectedTableTy->indexer->indexType;
-
-                if (FFlag::LuauBidirectionalInferenceCollectIndexerTypes)
-                {
-                    indexerKeyTypes.insert(tKey);
-                    indexerValueTypes.insert(tProp);
-                }
            }
            else
                LUAU_ASSERT(!"Unexpected");
        }

-        for (const auto& key : keysToDelete)
-        {
-            const AstArray<char>& s = key->value;
-            std::string keyStr{s.data, s.data + s.size};
-            tableTy->props.erase(keyStr);
-        }
-
        // Keys that the expectedType says we should have, but that aren't
        // specified by the AST fragment.
        //
@ -530,39 +436,9 @@ TypeId matchLiteralType(
        // have one too.
        // TODO: If the expected table also has an indexer, we might want to
        // push the expected indexer's types into it.
-        if (FFlag::LuauBidirectionalInferenceCollectIndexerTypes && expectedTableTy->indexer)
+        if (expectedTableTy->indexer && !tableTy->indexer)
        {
-            if (indexerValueTypes.size() > 0 && indexerKeyTypes.size() > 0)
-            {
-                TypeId inferredKeyType = builtinTypes->neverType;
-                TypeId inferredValueType = builtinTypes->neverType;
-                for (auto kt : indexerKeyTypes)
-                {
-                    auto simplified = simplifyUnion(builtinTypes, arena, inferredKeyType, kt);
-                    inferredKeyType = simplified.result;
-                }
-                for (auto vt : indexerValueTypes)
-                {
-                    auto simplified = simplifyUnion(builtinTypes, arena, inferredValueType, vt);
-                    inferredValueType = simplified.result;
-                }
-                tableTy->indexer = TableIndexer{inferredKeyType, inferredValueType};
-                auto keyCheck = subtyping->isSubtype(inferredKeyType, expectedTableTy->indexer->indexType, unifier->scope);
-                if (keyCheck.isSubtype)
-                    tableTy->indexer->indexType = expectedTableTy->indexer->indexType;
-                auto valueCheck = subtyping->isSubtype(inferredValueType, expectedTableTy->indexer->indexResultType, unifier->scope);
-                if (valueCheck.isSubtype)
-                    tableTy->indexer->indexResultType = expectedTableTy->indexer->indexResultType;
-            }
-            else
-                LUAU_ASSERT(indexerKeyTypes.empty() && indexerValueTypes.empty());
-        }
-        else
-        {
-            if (expectedTableTy->indexer && !tableTy->indexer)
-            {
-                tableTy->indexer = expectedTableTy->indexer;
-            }
+            tableTy->indexer = expectedTableTy->indexer;
        }
    }

--- a/Analysis/src/ToDot.cpp
+++ b/Analysis/src/ToDot.cpp
@ -299,9 +299,9 @@ void StateDot::visitChildren(TypeId ty, int index)
            finishNodeLabel(ty);
            finishNode();
        }
-        else if constexpr (std::is_same_v<T, ExternType>)
+        else if constexpr (std::is_same_v<T, ClassType>)
        {
-            formatAppend(result, "ExternType %s", t.name.c_str());
+            formatAppend(result, "ClassType %s", t.name.c_str());
            finishNodeLabel(ty);
            finishNode();

--- a/Analysis/src/ToString.cpp
+++ b/Analysis/src/ToString.cpp
@ -19,11 +19,8 @@
 #include <stdexcept>
 #include <string>

-LUAU_FASTFLAGVARIABLE(LuauEnableDenseTableAlias)
-
 LUAU_FASTFLAG(LuauSolverV2)
 LUAU_FASTFLAGVARIABLE(LuauSyntheticErrors)
-LUAU_FASTFLAGVARIABLE(LuauStringPartLengthLimit)

 /*
 * Enables increasing levels of verbosity for Luau type names when stringifying.
@ -123,7 +120,7 @@ struct FindCyclicTypes final : TypeVisitor
        return true;
    }

-    bool visit(TypeId ty, const ExternType&) override
+    bool visit(TypeId ty, const ClassType&) override
    {
        return false;
    }
@ -304,28 +301,6 @@ struct StringifierState
        emit(std::to_string(i).c_str());
    }

-    void emit(Polarity p)
-    {
-        switch (p)
-        {
-        case Polarity::None:
-            emit("  ");
-            break;
-        case Polarity::Negative:
-            emit(" -");
-            break;
-        case Polarity::Positive:
-            emit("+ ");
-            break;
-        case Polarity::Mixed:
-            emit("+-");
-            break;
-        default:
-            emit("!!");
-            break;
-        }
-    }
-
    void indent()
    {
        indentation += 4;
@ -507,8 +482,6 @@ struct TypeStringifier
            {
                state.emit("'");
                state.emit(state.getName(ty));
-                if (FInt::DebugLuauVerboseTypeNames >= 1)
-                    state.emit(ftv.polarity);
            }
            else
            {
@ -521,9 +494,6 @@ struct TypeStringifier
                state.emit("'");
                state.emit(state.getName(ty));

-                if (FInt::DebugLuauVerboseTypeNames >= 1)
-                    state.emit(ftv.polarity);
-
                if (!get<UnknownType>(upperBound))
                {
                    state.emit(" <: ");
@ -539,9 +509,6 @@ struct TypeStringifier

        state.emit(state.getName(ty));

-        if (FFlag::LuauSolverV2 && FInt::DebugLuauVerboseTypeNames >= 1)
-            state.emit(ftv.polarity);
-
        if (FInt::DebugLuauVerboseTypeNames >= 2)
        {
            state.emit("-");
@ -571,9 +538,6 @@ struct TypeStringifier
        else
            state.emit(state.getName(ty));

-        if (FInt::DebugLuauVerboseTypeNames >= 1)
-            state.emit(gtv.polarity);
-
        if (FInt::DebugLuauVerboseTypeNames >= 2)
        {
            state.emit("-");
@ -722,13 +686,7 @@ struct TypeStringifier
        if (ttv.boundTo)
            return stringify(*ttv.boundTo);

-        bool showName = !state.exhaustive;
-        if (FFlag::LuauEnableDenseTableAlias)
-        {
-            // if hide table alias expansions are enabled and there is a name found for the table, use it
-            showName = !state.exhaustive || state.opts.hideTableAliasExpansions;
-        }
-        if (showName)
+        if (!state.exhaustive)
        {
            if (ttv.name)
            {
@ -751,10 +709,6 @@ struct TypeStringifier
                stringify(ttv.instantiatedTypeParams, ttv.instantiatedTypePackParams);
                return;
            }
-        }
-
-        if (!state.exhaustive)
-        {
            if (ttv.syntheticName)
            {
                state.result.invalid = true;
@ -893,9 +847,9 @@ struct TypeStringifier
        state.emit(" }");
    }

-    void operator()(TypeId, const ExternType& etv)
+    void operator()(TypeId, const ClassType& ctv)
    {
-        state.emit(etv.name);
+        state.emit(ctv.name);
    }

    void operator()(TypeId, const AnyType&)
@ -923,9 +877,6 @@ struct TypeStringifier
        bool hasNonNilDisjunct = false;

        std::vector<std::string> results = {};
-        size_t resultsLength = 0;
-        bool lengthLimitHit = false;
-
        for (auto el : &uv)
        {
            el = follow(el);
@ -952,34 +903,14 @@ struct TypeStringifier
            if (needParens)
                state.emit(")");

-            if (FFlag::LuauStringPartLengthLimit)
-                resultsLength += state.result.name.length();
-
            results.push_back(std::move(state.result.name));
-
            state.result.name = std::move(saved);
-
-            if (FFlag::LuauStringPartLengthLimit)
-            {
-                lengthLimitHit = state.opts.maxTypeLength > 0 && resultsLength > state.opts.maxTypeLength;
-
-                if (lengthLimitHit)
-                    break;
-            }
        }

        state.unsee(&uv);

-        if (FFlag::LuauStringPartLengthLimit)
-        {
-            if (!lengthLimitHit && !FFlag::DebugLuauToStringNoLexicalSort)
-                std::sort(results.begin(), results.end());
-        }
-        else
-        {
-            if (!FFlag::DebugLuauToStringNoLexicalSort)
-                std::sort(results.begin(), results.end());
-        }
+        if (!FFlag::DebugLuauToStringNoLexicalSort)
+            std::sort(results.begin(), results.end());

        if (optional && results.size() > 1)
            state.emit("(");
@ -1023,9 +954,6 @@ struct TypeStringifier
        }

        std::vector<std::string> results = {};
-        size_t resultsLength = 0;
-        bool lengthLimitHit = false;
-
        for (auto el : uv.parts)
        {
            el = follow(el);
@ -1042,34 +970,14 @@ struct TypeStringifier
            if (needParens)
                state.emit(")");

-            if (FFlag::LuauStringPartLengthLimit)
-                resultsLength += state.result.name.length();
-
            results.push_back(std::move(state.result.name));
-
            state.result.name = std::move(saved);
-
-            if (FFlag::LuauStringPartLengthLimit)
-            {
-                lengthLimitHit = state.opts.maxTypeLength > 0 && resultsLength > state.opts.maxTypeLength;
-
-                if (lengthLimitHit)
-                    break;
-            }
        }

        state.unsee(&uv);

-        if (FFlag::LuauStringPartLengthLimit)
-        {
-            if (!lengthLimitHit && !FFlag::DebugLuauToStringNoLexicalSort)
-                std::sort(results.begin(), results.end());
-        }
-        else
-        {
-            if (!FFlag::DebugLuauToStringNoLexicalSort)
-                std::sort(results.begin(), results.end());
-        }
+        if (!FFlag::DebugLuauToStringNoLexicalSort)
+            std::sort(results.begin(), results.end());

        bool first = true;
        bool shouldPlaceOnNewlines = results.size() > state.opts.compositeTypesSingleLineLimit || isOverloadedFunction(ty);
@ -1314,9 +1222,6 @@ struct TypePackStringifier
            state.emit(state.getName(tp));
        }

-        if (FInt::DebugLuauVerboseTypeNames >= 1)
-            state.emit(pack.polarity);
-
        if (FInt::DebugLuauVerboseTypeNames >= 2)
        {
            state.emit("-");
@ -1336,9 +1241,6 @@ struct TypePackStringifier
            state.emit("free-");
        state.emit(state.getName(tp));

-        if (FInt::DebugLuauVerboseTypeNames >= 1)
-            state.emit(pack.polarity);
-
        if (FInt::DebugLuauVerboseTypeNames >= 2)
        {
            state.emit("-");
@ -1963,8 +1865,6 @@ std::string toString(const Constraint& constraint, ToStringOptions& opts)
        }
        else if constexpr (std::is_same_v<T, EqualityConstraint>)
            return "equality: " + tos(c.resultType) + " ~ " + tos(c.assignmentType);
-        else if constexpr (std::is_same_v<T, TableCheckConstraint>)
-            return "table_check " + tos(c.expectedType) + " :> " + tos(c.exprType);
        else
            static_assert(always_false_v<T>, "Non-exhaustive constraint switch");
    };
--- a/Analysis/src/TopoSortStatements.cpp
+++ b/Analysis/src/TopoSortStatements.cpp
@ -41,8 +41,6 @@
 #include <stdexcept>
 #include <optional>

-LUAU_FASTFLAG(LuauStoreReturnTypesAsPackOnAst)
-
 namespace Luau
 {

@ -299,11 +297,6 @@ struct ArcCollector : public AstVisitor
            add(*name);
        return true;
    }
-
-    bool visit(AstTypePack* node) override
-    {
-        return FFlag::LuauStoreReturnTypesAsPackOnAst;
-    }
 };

 struct ContainsFunctionCall : public AstVisitor
--- a/Analysis/src/Transpiler.cpp
+++ b/Analysis/src/Transpiler.cpp
--- a/Analysis/src/TxnLog.cpp
+++ b/Analysis/src/TxnLog.cpp
@ -407,6 +407,41 @@ PendingTypePack* TxnLog::changeLevel(TypePackId tp, TypeLevel newLevel)
    return newTp;
 }

+PendingType* TxnLog::changeScope(TypeId ty, NotNull<Scope> newScope)
+{
+    LUAU_ASSERT(get<FreeType>(ty) || get<TableType>(ty) || get<FunctionType>(ty));
+
+    PendingType* newTy = queue(ty);
+    if (FreeType* ftv = Luau::getMutable<FreeType>(newTy))
+    {
+        ftv->scope = newScope;
+    }
+    else if (TableType* ttv = Luau::getMutable<TableType>(newTy))
+    {
+        LUAU_ASSERT(ttv->state == TableState::Free || ttv->state == TableState::Generic);
+        ttv->scope = newScope;
+    }
+    else if (FunctionType* ftv = Luau::getMutable<FunctionType>(newTy))
+    {
+        ftv->scope = newScope;
+    }
+
+    return newTy;
+}
+
+PendingTypePack* TxnLog::changeScope(TypePackId tp, NotNull<Scope> newScope)
+{
+    LUAU_ASSERT(get<FreeTypePack>(tp));
+
+    PendingTypePack* newTp = queue(tp);
+    if (FreeTypePack* ftp = Luau::getMutable<FreeTypePack>(newTp))
+    {
+        ftp->scope = newScope;
+    }
+
+    return newTp;
+}
+
 PendingType* TxnLog::changeIndexer(TypeId ty, std::optional<TableIndexer> indexer)
 {
    LUAU_ASSERT(get<TableType>(ty));
--- a/Analysis/src/Type.cpp
+++ b/Analysis/src/Type.cpp
@ -27,7 +27,6 @@ LUAU_FASTINTVARIABLE(LuauTypeMaximumStringifierLength, 500)
 LUAU_FASTINTVARIABLE(LuauTableTypeMaximumStringifierLength, 0)
 LUAU_FASTINT(LuauTypeInferRecursionLimit)
 LUAU_FASTFLAG(LuauInstantiateInSubtyping)
-LUAU_FASTFLAGVARIABLE(LuauFreeTypesMustHaveBounds)

 namespace Luau
 {
@ -282,8 +281,8 @@ std::optional<TypeId> getMetatable(TypeId type, NotNull<BuiltinTypes> builtinTyp

    if (const MetatableType* mtType = get<MetatableType>(type))
        return mtType->metatable;
-    else if (const ExternType* externType = get<ExternType>(type))
-        return externType->metatable;
+    else if (const ClassType* classType = get<ClassType>(type))
+        return classType->metatable;
    else if (isString(type))
    {
        auto ptv = get<PrimitiveType>(builtinTypes->stringType);
@ -346,10 +345,10 @@ std::optional<ModuleName> getDefinitionModuleName(TypeId type)
        if (ftv->definition)
            return ftv->definition->definitionModuleName;
    }
-    else if (auto etv = get<ExternType>(type))
+    else if (auto ctv = get<ClassType>(type))
    {
-        if (!etv->definitionModuleName.empty())
-            return etv->definitionModuleName;
+        if (!ctv->definitionModuleName.empty())
+            return ctv->definitionModuleName;
    }

    return std::nullopt;
@ -479,28 +478,30 @@ bool hasLength(TypeId ty, DenseHashSet<TypeId>& seen, int* recursionCount)
    return false;
 }

-// New constructors
-FreeType::FreeType(TypeLevel level, TypeId lowerBound, TypeId upperBound)
+FreeType::FreeType(TypeLevel level)
    : index(Unifiable::freshIndex())
    , level(level)
-    , lowerBound(lowerBound)
-    , upperBound(upperBound)
+    , scope(nullptr)
 {
 }

-FreeType::FreeType(Scope* scope, TypeId lowerBound, TypeId upperBound, Polarity polarity)
+FreeType::FreeType(Scope* scope)
    : index(Unifiable::freshIndex())
+    , level{}
    , scope(scope)
-    , lowerBound(lowerBound)
-    , upperBound(upperBound)
-    , polarity(polarity)
 {
 }

-FreeType::FreeType(Scope* scope, TypeLevel level, TypeId lowerBound, TypeId upperBound)
+FreeType::FreeType(Scope* scope, TypeLevel level)
    : index(Unifiable::freshIndex())
    , level(level)
    , scope(scope)
+{
+}
+
+FreeType::FreeType(Scope* scope, TypeId lowerBound, TypeId upperBound)
+    : index(Unifiable::freshIndex())
+    , scope(scope)
    , lowerBound(lowerBound)
    , upperBound(upperBound)
 {
@ -519,18 +520,16 @@ GenericType::GenericType(TypeLevel level)
 {
 }

-GenericType::GenericType(const Name& name, Polarity polarity)
+GenericType::GenericType(const Name& name)
    : index(Unifiable::freshIndex())
    , name(name)
    , explicitName(true)
-    , polarity(polarity)
 {
 }

-GenericType::GenericType(Scope* scope, Polarity polarity)
+GenericType::GenericType(Scope* scope)
    : index(Unifiable::freshIndex())
    , scope(scope)
-    , polarity(polarity)
 {
 }

@ -608,6 +607,23 @@ FunctionType::FunctionType(TypeLevel level, TypePackId argTypes, TypePackId retT
 {
 }

+FunctionType::FunctionType(
+    TypeLevel level,
+    Scope* scope,
+    TypePackId argTypes,
+    TypePackId retTypes,
+    std::optional<FunctionDefinition> defn,
+    bool hasSelf
+)
+    : definition(std::move(defn))
+    , level(level)
+    , scope(scope)
+    , argTypes(argTypes)
+    , retTypes(retTypes)
+    , hasSelf(hasSelf)
+{
+}
+
 FunctionType::FunctionType(
    std::vector<TypeId> generics,
    std::vector<TypePackId> genericPacks,
@ -644,6 +660,27 @@ FunctionType::FunctionType(
 {
 }

+FunctionType::FunctionType(
+    TypeLevel level,
+    Scope* scope,
+    std::vector<TypeId> generics,
+    std::vector<TypePackId> genericPacks,
+    TypePackId argTypes,
+    TypePackId retTypes,
+    std::optional<FunctionDefinition> defn,
+    bool hasSelf
+)
+    : definition(std::move(defn))
+    , generics(generics)
+    , genericPacks(genericPacks)
+    , level(level)
+    , scope(scope)
+    , argTypes(argTypes)
+    , retTypes(retTypes)
+    , hasSelf(hasSelf)
+{
+}
+
 Property::Property() {}

 Property::Property(
@ -989,7 +1026,7 @@ BuiltinTypes::BuiltinTypes()
    , threadType(arena->addType(Type{PrimitiveType{PrimitiveType::Thread}, /*persistent*/ true}))
    , bufferType(arena->addType(Type{PrimitiveType{PrimitiveType::Buffer}, /*persistent*/ true}))
    , functionType(arena->addType(Type{PrimitiveType{PrimitiveType::Function}, /*persistent*/ true}))
-    , externType(arena->addType(Type{ExternType{"class", {}, std::nullopt, std::nullopt, {}, {}, {}, {}}, /*persistent*/ true}))
+    , classType(arena->addType(Type{ClassType{"class", {}, std::nullopt, std::nullopt, {}, {}, {}, {}}, /*persistent*/ true}))
    , tableType(arena->addType(Type{PrimitiveType{PrimitiveType::Table}, /*persistent*/ true}))
    , emptyTableType(arena->addType(Type{TableType{TableState::Sealed, TypeLevel{}, nullptr}, /*persistent*/ true}))
    , trueType(arena->addType(Type{SingletonType{BooleanSingleton{true}}, /*persistent*/ true}))
@ -1001,7 +1038,6 @@ BuiltinTypes::BuiltinTypes()
    , noRefineType(arena->addType(Type{NoRefineType{}, /*persistent*/ true}))
    , falsyType(arena->addType(Type{UnionType{{falseType, nilType}}, /*persistent*/ true}))
    , truthyType(arena->addType(Type{NegationType{falsyType}, /*persistent*/ true}))
-    , notNilType(arena->addType(Type{NegationType{nilType}, /*persistent*/ true}))
    , optionalNumberType(arena->addType(Type{UnionType{{numberType, nilType}}, /*persistent*/ true}))
    , optionalStringType(arena->addType(Type{UnionType{{stringType, nilType}}, /*persistent*/ true}))
    , emptyTypePack(arena->addTypePack(TypePackVar{TypePack{{}}, /*persistent*/ true}))
@ -1080,9 +1116,9 @@ void persist(TypeId ty)
                queue.push_back(ttv->indexer->indexResultType);
            }
        }
-        else if (auto etv= get<ExternType>(t))
+        else if (auto ctv = get<ClassType>(t))
        {
-            for (const auto& [_name, prop] : etv->props)
+            for (const auto& [_name, prop] : ctv->props)
                queue.push_back(prop.type());
        }
        else if (auto utv = get<UnionType>(t))
@ -1182,7 +1218,7 @@ std::optional<TypeLevel> getLevel(TypePackId tp)
        return std::nullopt;
 }

-const Property* lookupExternTypeProp(const ExternType* cls, const Name& name)
+const Property* lookupClassProp(const ClassType* cls, const Name& name)
 {
    while (cls)
    {
@ -1191,7 +1227,7 @@ const Property* lookupExternTypeProp(const ExternType* cls, const Name& name)
            return &it->second;

        if (cls->parent)
-            cls = get<ExternType>(*cls->parent);
+            cls = get<ClassType>(*cls->parent);
        else
            return nullptr;

@ -1201,7 +1237,7 @@ const Property* lookupExternTypeProp(const ExternType* cls, const Name& name)
    return nullptr;
 }

-bool isSubclass(const ExternType* cls, const ExternType* parent)
+bool isSubclass(const ClassType* cls, const ClassType* parent)
 {
    while (cls)
    {
@ -1210,7 +1246,7 @@ bool isSubclass(const ExternType* cls, const ExternType* parent)
        else if (!cls->parent)
            return false;

-        cls = get<ExternType>(*cls->parent);
+        cls = get<ClassType>(*cls->parent);
        LUAU_ASSERT(cls);
    }

@ -1247,9 +1283,9 @@ IntersectionTypeIterator end(const IntersectionType* itv)
    return IntersectionTypeIterator{};
 }

-TypeId freshType(NotNull<TypeArena> arena, NotNull<BuiltinTypes> builtinTypes, Scope* scope, Polarity polarity)
+TypeId freshType(NotNull<TypeArena> arena, NotNull<BuiltinTypes> builtinTypes, Scope* scope)
 {
-    return arena->addType(FreeType{scope, builtinTypes->neverType, builtinTypes->unknownType, polarity});
+    return arena->addType(FreeType{scope, builtinTypes->neverType, builtinTypes->unknownType});
 }

 std::vector<TypeId> filterMap(TypeId type, TypeIdPredicate predicate)
@ -1279,8 +1315,8 @@ static Tags* getTags(TypeId ty)
        return &ftv->tags;
    else if (auto ttv = getMutable<TableType>(ty))
        return &ttv->tags;
-    else if (auto etv = getMutable<ExternType>(ty))
-        return &etv->tags;
+    else if (auto ctv = getMutable<ClassType>(ty))
+        return &ctv->tags;

    return nullptr;
 }
@ -1310,19 +1346,19 @@ bool hasTag(TypeId ty, const std::string& tagName)
 {
    ty = follow(ty);

-    // We special case extern types because getTags only returns a pointer to one vector of tags.
-    // But extern types has multiple vector of tags, represented throughout the hierarchy.
-    if (auto etv = get<ExternType>(ty))
+    // We special case classes because getTags only returns a pointer to one vector of tags.
+    // But classes has multiple vector of tags, represented throughout the hierarchy.
+    if (auto ctv = get<ClassType>(ty))
    {
-        while (etv)
+        while (ctv)
        {
-            if (hasTag(etv->tags, tagName))
+            if (hasTag(ctv->tags, tagName))
                return true;
-            else if (!etv->parent)
+            else if (!ctv->parent)
                return false;

-            etv = get<ExternType>(*etv->parent);
-            LUAU_ASSERT(etv);
+            ctv = get<ClassType>(*ctv->parent);
+            LUAU_ASSERT(ctv);
        }
    }
    else if (auto tags = getTags(ty))
--- a/Show more
+++ b/Show more