diff --git a/Cargo.lock b/Cargo.lock
index 89ee282..de492ab 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -807,7 +807,7 @@ checksum = "f2b99bf03862d7f545ebc28ddd33a665b50865f4dfd84031a393823879bd4c54"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.72",
+ "syn 2.0.79",
 ]
 
 [[package]]
diff --git a/crates/lune-std-ffi/README.md b/crates/lune-std-ffi/README.md
new file mode 100644
index 0000000..1b8c6ca
--- /dev/null
+++ b/crates/lune-std-ffi/README.md
@@ -0,0 +1,79 @@
+# `lune-std-ffi`
+
+## Code structure
+
+### /c
+
+Define C-ABI type information and provide conversion and casting
+
+- [**Struct ` CArrInfo`:**](./src/c/struct_info.rs) Represents C Array type
+- [**Struct ` CPtrInfo`:**](./src/c/ptr_info.rs) Represents C Pointer type
+- [**Struct ` CFnInfo`:**](./src/c/fn_info.rs) Represents C Function signature
+  provide CallableData and ClosureData creation
+- [**Struct ` CStructInfo`:**](./src/c/struct_info.rs) Represents C Struct type
+- [**Struct ` CTypeInfo<T>`:**](./src/c/type_info.rs) Represents C type, extended in `/c/types`
+
+#### /c/types
+
+Export fixed-size source time known types and non-fixed compile time known types
+Implememt type-casting for all CTypes
+
+**Mod `ctype_helper`:**
+
+- **Function `get_conv`:**
+  get _FfiConvert_ from some ctype userdata, used for struct and array conversion
+- **Function `get_size`:**
+  get size from some ctype userdata, used for call return and arguments boundary checking
+- **Function `get_name`:**
+  get type name from some ctype userdata, used for pretty-print
+- **Function `get_middle_type`:**
+  get **`libffi::middle::Type`:** from some ctype userdata
+- **Function `is_ctype`:** check userdata is ctype
+
+---
+
+### /data
+
+**Structs:** Provide memory userdata
+
+- [**Struct `BoxData`:**](./src/data/box_data/mod.rs) A heap allocated memory with user definable lifetime
+- [**Struct `LibData`:**](./src/data/lib_data.rs) A dynamic opened library
+- [**Struct `RefData`:**](./src/data/ref_data/mod.rs) A reference that can be used for receiving return data from external function or pass pointer arguments
+
+**Structs:** Provide function(pointer) userdata
+
+- [**Struct `CallableData`:**](./src/data/callable_data.rs) A callable function, which can be created from function pointer
+- [**Struct `ClosureData`:**](./src/data/closure_data.rs) A closure pointer, which can be created from lua function and can be used for callback
+
+---
+
+### /ffi
+
+**Traits:** Provide ABI shared common type information trait
+
+- **Trait `FfiSize`**
+- **Trait `FfiSignedness`**
+- **Trait `FfiConvert`:** Provide read LuaValue from FfiData or write LuaValue into FfiData
+
+**Trait `FfiData`:** Provide common data handle, including methods below
+
+- **Method `check_boundary`:** check boundary with offset and size
+- **Method `get_pointer`:** returns raw pointer `*mut ()`
+- **Method `is_writable`**
+- **Method `is_readable`**
+
+> Note: `GetFfiData` trait in `data/mod.rs` provides `AnyUserData.get_data_handle() -> FfiData` method
+
+**Mods:** Provide common helper functions
+
+- **`association.rs`:** GC utility, used for inner, ret and arg type holding in subtype
+- **`bit_mask.rs`:** u8 bitfield helper
+- **`cast.rs`:** library
+  - **Function `num_cast<From, Into>(from: FfiData, from: FfiData)`:**
+    Cast number type value inno another number type
+- **`libffi_helper.rs`:**
+  - **Const `FFI_STATUS_NAMES`:** Used for ffi_status stringify
+  - **Function `get_ensured_size`:** Returns ensured ffi_type size
+  - **Const `SIEE_OF_POINTER`:** Platform specific pointer size (Compile time known)
+
+## TODO
diff --git a/crates/lune-std-ffi/src/c/c_arr.rs b/crates/lune-std-ffi/src/c/arr_info.rs
similarity index 78%
rename from crates/lune-std-ffi/src/c/c_arr.rs
rename to crates/lune-std-ffi/src/c/arr_info.rs
index c4bbfc6..088fe34 100644
--- a/crates/lune-std-ffi/src/c/c_arr.rs
+++ b/crates/lune-std-ffi/src/c/arr_info.rs
@@ -3,12 +3,11 @@ use std::cell::Ref;
 use libffi::middle::Type;
 use mlua::prelude::*;
 
-use super::{association_names::CARR_INNER, c_helper, method_provider};
-use crate::ffi::{
-    ffi_association::{get_association, set_association},
-    NativeConvert, NativeData, NativeSize,
+use super::{association_names::CARR_INNER, helper, method_provider};
+use crate::{
+    data::{FfiConvert, FfiData, FfiSize},
+    ffi::{association, libffi_helper::get_ensured_size},
 };
-use crate::libffi_helper::get_ensured_size;
 
 // This is a series of some type.
 // It provides the final size and the offset of the index,
@@ -19,19 +18,19 @@ use crate::libffi_helper::get_ensured_size;
 // We can simply provide array type with struct.
 // See: https://stackoverflow.com/a/43525176
 
-pub struct CArr {
+pub struct CArrInfo {
     struct_type: Type,
     length: usize,
     size: usize,
     inner_size: usize,
-    inner_conv: *const dyn NativeConvert,
+    inner_conv: *const dyn FfiConvert,
 }
 
-impl CArr {
+impl CArrInfo {
     pub fn new(
         element_type: Type,
         length: usize,
-        inner_conv: *const dyn NativeConvert,
+        inner_conv: *const dyn FfiConvert,
     ) -> LuaResult<Self> {
         let inner_size = get_ensured_size(element_type.as_raw_ptr())?;
         let struct_type = Type::structure(vec![element_type.clone(); length]);
@@ -51,11 +50,11 @@ impl CArr {
         type_userdata: &LuaAnyUserData<'lua>,
         length: usize,
     ) -> LuaResult<LuaAnyUserData<'lua>> {
-        let fields = c_helper::get_middle_type(type_userdata)?;
-        let conv = unsafe { c_helper::get_conv(type_userdata)? };
+        let fields = helper::get_middle_type(type_userdata)?;
+        let conv = unsafe { helper::get_conv(type_userdata)? };
         let carr = lua.create_userdata(Self::new(fields, length, conv)?)?;
 
-        set_association(lua, CARR_INNER, &carr, type_userdata)?;
+        association::set(lua, CARR_INNER, &carr, type_userdata)?;
         Ok(carr)
     }
 
@@ -70,13 +69,13 @@ impl CArr {
     // Stringify for pretty printing like:
     // <CArr( u8, length = 8 )>
     pub fn stringify(lua: &Lua, userdata: &LuaAnyUserData) -> LuaResult<String> {
-        let this = userdata.borrow::<CArr>()?;
+        let this = userdata.borrow::<CArrInfo>()?;
         if let Some(LuaValue::UserData(inner_userdata)) =
-            get_association(lua, CARR_INNER, userdata)?
+            association::get(lua, CARR_INNER, userdata)?
         {
             Ok(format!(
                 " {}, length = {} ",
-                c_helper::pretty_format(lua, &inner_userdata)?,
+                helper::pretty_format(lua, &inner_userdata)?,
                 this.length,
             ))
         } else {
@@ -85,18 +84,18 @@ impl CArr {
     }
 }
 
-impl NativeSize for CArr {
+impl FfiSize for CArrInfo {
     fn get_size(&self) -> usize {
         self.size
     }
 }
-impl NativeConvert for CArr {
+impl FfiConvert for CArrInfo {
     // FIXME: FfiBox, FfiRef support required
-    unsafe fn luavalue_into<'lua>(
+    unsafe fn value_into_data<'lua>(
         &self,
         lua: &'lua Lua,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let LuaValue::Table(ref table) = value else {
@@ -106,7 +105,7 @@ impl NativeConvert for CArr {
             let field_offset = (i * self.inner_size) as isize;
             let data: LuaValue = table.get(i + 1)?;
 
-            self.inner_conv.as_ref().unwrap().luavalue_into(
+            self.inner_conv.as_ref().unwrap().value_into_data(
                 lua,
                 field_offset + offset,
                 data_handle,
@@ -116,18 +115,18 @@ impl NativeConvert for CArr {
         Ok(())
     }
 
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
         let table = lua.create_table_with_capacity(self.length, 0)?;
         for i in 0..self.length {
             let field_offset = (i * self.inner_size) as isize;
             table.set(
                 i + 1,
-                self.inner_conv.as_ref().unwrap().luavalue_from(
+                self.inner_conv.as_ref().unwrap().value_from_data(
                     lua,
                     field_offset + offset,
                     data_handle,
@@ -138,12 +137,12 @@ impl NativeConvert for CArr {
     }
 }
 
-impl LuaUserData for CArr {
+impl LuaUserData for CArrInfo {
     fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
         fields.add_field_method_get("size", |_, this| Ok(this.get_size()));
         fields.add_field_method_get("length", |_, this| Ok(this.get_length()));
         fields.add_field_function_get("inner", |lua, this: LuaAnyUserData| {
-            let inner: LuaValue = get_association(lua, CARR_INNER, this)?
+            let inner: LuaValue = association::get(lua, CARR_INNER, this)?
                 // It shouldn't happen.
                 .ok_or_else(|| LuaError::external("inner field not found"))?;
             Ok(inner)
diff --git a/crates/lune-std-ffi/src/c/c_string.rs b/crates/lune-std-ffi/src/c/c_string.rs
deleted file mode 100644
index 9c3d777..0000000
--- a/crates/lune-std-ffi/src/c/c_string.rs
+++ /dev/null
@@ -1,8 +0,0 @@
-// This is a string type that can be given to an external function.
-// To be exact, it converts the Lua string into a c_char array and puts it in the box.
-// For this part, initially, i wanted to allow box("lua string"),
-// but separated it for clarity.
-// This also allows operations such as ffi.string:intoBox().
-// (Write a string to an already existing box)
-
-// FIXME: use buffer instead?
diff --git a/crates/lune-std-ffi/src/c/c_func.rs b/crates/lune-std-ffi/src/c/fn_info.rs
similarity index 66%
rename from crates/lune-std-ffi/src/c/c_func.rs
rename to crates/lune-std-ffi/src/c/fn_info.rs
index b323e3e..b2942a4 100644
--- a/crates/lune-std-ffi/src/c/c_func.rs
+++ b/crates/lune-std-ffi/src/c/fn_info.rs
@@ -5,13 +5,11 @@ use mlua::prelude::*;
 
 use super::{
     association_names::{CALLABLE_CFN, CALLABLE_REF, CFN_ARGS, CFN_RESULT},
-    c_helper, method_provider,
+    helper, method_provider,
 };
-use crate::ffi::{
-    bit_mask::u8_test_not,
-    ffi_association::{get_association, set_association},
-    FfiCallable, FfiRef, FfiRefFlag, NativeArgInfo, NativeData, NativeResultInfo, NativeSignedness,
-    NativeSize,
+use crate::{
+    data::{CallableData, RefData, RefDataFlag},
+    ffi::{association, bit_mask::*, FfiArgInfo, FfiData, FfiResultInfo, FfiSignedness, FfiSize},
 };
 
 // cfn is a type declaration for a function.
@@ -30,29 +28,29 @@ use crate::ffi::{
 // The name cfn is intentional. This is because any *c_void is
 // moved to a Lua function or vice versa.
 
-pub struct CFunc {
+pub struct CFnInfo {
     cif: Cif,
-    arg_info_list: Vec<NativeArgInfo>,
-    result_info: NativeResultInfo,
+    arg_info_list: Vec<FfiArgInfo>,
+    result_info: FfiResultInfo,
 }
 
-impl NativeSignedness for CFunc {
+impl FfiSignedness for CFnInfo {
     fn get_signedness(&self) -> bool {
         false
     }
 }
-impl NativeSize for CFunc {
+impl FfiSize for CFnInfo {
     fn get_size(&self) -> usize {
         size_of::<*mut ()>()
     }
 }
 
-impl CFunc {
+impl CFnInfo {
     pub fn new(
         args: Vec<Type>,
         ret: Type,
-        arg_info_list: Vec<NativeArgInfo>,
-        result_info: NativeResultInfo,
+        arg_info_list: Vec<FfiArgInfo>,
+        result_info: FfiResultInfo,
     ) -> LuaResult<Self> {
         // let cif = ;
 
@@ -68,29 +66,29 @@ impl CFunc {
         arg_table: LuaTable,
         ret: LuaAnyUserData,
     ) -> LuaResult<LuaAnyUserData<'lua>> {
-        let args_types = c_helper::get_middle_type_list(&arg_table)?;
-        let ret_type = c_helper::get_middle_type(&ret)?;
+        let args_types = helper::get_middle_type_list(&arg_table)?;
+        let ret_type = helper::get_middle_type(&ret)?;
 
         let arg_len = arg_table.raw_len();
-        let mut arg_info_list = Vec::<NativeArgInfo>::with_capacity(arg_len);
+        let mut arg_info_list = Vec::<FfiArgInfo>::with_capacity(arg_len);
         for index in 0..arg_len {
-            let userdata = c_helper::get_userdata(arg_table.raw_get(index + 1)?)?;
-            arg_info_list.push(NativeArgInfo {
-                conv: unsafe { c_helper::get_conv(&userdata)? },
-                size: c_helper::get_size(&userdata)?,
+            let userdata = helper::get_userdata(arg_table.raw_get(index + 1)?)?;
+            arg_info_list.push(FfiArgInfo {
+                conv: unsafe { helper::get_conv(&userdata)? },
+                size: helper::get_size(&userdata)?,
             });
         }
-        let result_info = NativeResultInfo {
-            conv: unsafe { c_helper::get_conv(&ret)? },
-            size: c_helper::get_size(&ret)?,
+        let result_info = FfiResultInfo {
+            conv: unsafe { helper::get_conv(&ret)? },
+            size: helper::get_size(&ret)?,
         };
 
         let cfn =
             lua.create_userdata(Self::new(args_types, ret_type, arg_info_list, result_info)?)?;
 
         // Create association to hold argument and result type
-        set_association(lua, CFN_ARGS, &cfn, arg_table)?;
-        set_association(lua, CFN_RESULT, &cfn, ret)?;
+        association::set(lua, CFN_ARGS, &cfn, arg_table)?;
+        association::set(lua, CFN_RESULT, &cfn, ret)?;
 
         Ok(cfn)
     }
@@ -100,13 +98,13 @@ impl CFunc {
     pub fn stringify(lua: &Lua, userdata: &LuaAnyUserData) -> LuaResult<String> {
         let mut result = String::from(" (");
         if let (Some(LuaValue::Table(arg_table)), Some(LuaValue::UserData(result_userdata))) = (
-            get_association(lua, CFN_ARGS, userdata)?,
-            get_association(lua, CFN_RESULT, userdata)?,
+            association::get(lua, CFN_ARGS, userdata)?,
+            association::get(lua, CFN_RESULT, userdata)?,
         ) {
             let len = arg_table.raw_len();
             for arg_index in 1..=len {
                 let arg_userdata: LuaAnyUserData = arg_table.raw_get(arg_index)?;
-                let pretty_formatted = c_helper::pretty_format(lua, &arg_userdata)?;
+                let pretty_formatted = helper::pretty_format(lua, &arg_userdata)?;
                 result.push_str(
                     (if len == arg_index {
                         pretty_formatted
@@ -117,7 +115,7 @@ impl CFunc {
                 );
             }
             result.push_str(
-                format!(") -> {} ", c_helper::pretty_format(lua, &result_userdata)?,).as_str(),
+                format!(") -> {} ", helper::pretty_format(lua, &result_userdata)?,).as_str(),
             );
             Ok(result)
         } else {
@@ -126,7 +124,7 @@ impl CFunc {
     }
 }
 
-impl LuaUserData for CFunc {
+impl LuaUserData for CFnInfo {
     fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
         // Subtype
         method_provider::provide_ptr_info(methods);
@@ -142,19 +140,19 @@ impl LuaUserData for CFunc {
         methods.add_function(
             "callable",
             |lua, (cfn, function_ref): (LuaAnyUserData, LuaAnyUserData)| {
-                let this = cfn.borrow::<CFunc>()?;
+                let this = cfn.borrow::<CFnInfo>()?;
 
-                if !function_ref.is::<FfiRef>() {
+                if !function_ref.is::<RefData>() {
                     return Err(LuaError::external("argument 0 must be ffiref"));
                 }
 
-                let ffi_ref = function_ref.borrow::<FfiRef>()?;
-                if u8_test_not(ffi_ref.flags, FfiRefFlag::Function.value()) {
+                let ffi_ref = function_ref.borrow::<RefData>()?;
+                if u8_test_not(ffi_ref.flags, RefDataFlag::Function.value()) {
                     return Err(LuaError::external("not a function ref"));
                 }
 
                 let callable = lua.create_userdata(unsafe {
-                    FfiCallable::new(
+                    CallableData::new(
                         this.cif.as_raw_ptr(),
                         ptr::from_ref(&this.arg_info_list),
                         ptr::from_ref(&this.result_info),
@@ -162,8 +160,8 @@ impl LuaUserData for CFunc {
                     )
                 })?;
 
-                set_association(lua, CALLABLE_CFN, &callable, cfn.clone())?;
-                set_association(lua, CALLABLE_REF, &callable, function_ref.clone())?;
+                association::set(lua, CALLABLE_CFN, &callable, cfn.clone())?;
+                association::set(lua, CALLABLE_REF, &callable, function_ref.clone())?;
 
                 Ok(callable)
             },
diff --git a/crates/lune-std-ffi/src/c/c_helper.rs b/crates/lune-std-ffi/src/c/helper.rs
similarity index 68%
rename from crates/lune-std-ffi/src/c/c_helper.rs
rename to crates/lune-std-ffi/src/c/helper.rs
index fcede75..7f7b5ae 100644
--- a/crates/lune-std-ffi/src/c/c_helper.rs
+++ b/crates/lune-std-ffi/src/c/helper.rs
@@ -2,8 +2,8 @@ use libffi::middle::Type;
 use lune_utils::fmt::{pretty_format_value, ValueFormatConfig};
 use mlua::prelude::*;
 
-use super::{c_type_helper, CArr, CFunc, CPtr, CStruct};
-use crate::ffi::{FfiBox, GetNativeData, NativeConvert, NativeSize};
+use super::{ctype_helper, CArrInfo, CFnInfo, CPtrInfo, CStructInfo};
+use crate::data::{BoxData, FfiConvert, FfiSize, GetFfiData};
 
 pub mod method_provider {
     use super::*;
@@ -20,8 +20,8 @@ pub mod method_provider {
     where
         M: LuaUserDataMethods<'lua, Target>,
     {
-        methods.add_function("ptrInfo", |lua, this: LuaAnyUserData| {
-            CPtr::from_userdata(lua, &this)
+        methods.add_function("pointerInfo", |lua, this: LuaAnyUserData| {
+            CPtrInfo::from_userdata(lua, &this)
         });
     }
 
@@ -29,14 +29,14 @@ pub mod method_provider {
     where
         M: LuaUserDataMethods<'lua, Target>,
     {
-        methods.add_function("arrInfo", |lua, (this, length): (LuaAnyUserData, usize)| {
-            CArr::from_userdata(lua, &this, length)
+        methods.add_function("ArrInfo", |lua, (this, length): (LuaAnyUserData, usize)| {
+            CArrInfo::from_userdata(lua, &this, length)
         });
     }
 
     pub fn provide_from_data<'lua, Target, M>(methods: &mut M)
     where
-        Target: NativeSize + NativeConvert,
+        Target: FfiSize + FfiConvert,
         M: LuaUserDataMethods<'lua, Target>,
     {
         methods.add_method(
@@ -52,14 +52,14 @@ pub mod method_provider {
                     return Err(LuaError::external("Unreadable data handle"));
                 }
 
-                unsafe { this.luavalue_from(lua, offset, data_handle) }
+                unsafe { this.value_from_data(lua, offset, data_handle) }
             },
         );
     }
 
     pub fn provide_into_data<'lua, Target, M>(methods: &mut M)
     where
-        Target: NativeSize + NativeConvert,
+        Target: FfiSize + FfiConvert,
         M: LuaUserDataMethods<'lua, Target>,
     {
         methods.add_method(
@@ -76,19 +76,19 @@ pub mod method_provider {
                     return Err(LuaError::external("Unwritable data handle"));
                 }
 
-                unsafe { this.luavalue_into(lua, offset, data_handle, value) }
+                unsafe { this.value_into_data(lua, offset, data_handle, value) }
             },
         );
     }
 
     pub fn provide_box<'lua, Target, M>(methods: &mut M)
     where
-        Target: NativeSize + NativeConvert,
+        Target: FfiSize + FfiConvert,
         M: LuaUserDataMethods<'lua, Target>,
     {
         methods.add_method("box", |lua, this, table: LuaValue| {
-            let result = lua.create_userdata(FfiBox::new(this.get_size()))?;
-            unsafe { this.luavalue_into(lua, 0, &result.get_data_handle()?, table)? };
+            let result = lua.create_userdata(BoxData::new(this.get_size()))?;
+            unsafe { this.value_into_data(lua, 0, &result.get_data_handle()?, table)? };
             Ok(result)
         });
     }
@@ -109,22 +109,22 @@ pub fn get_userdata(value: LuaValue) -> LuaResult<LuaAnyUserData> {
 // this is intended to avoid lookup userdata and lua table every time. (eg: struct)
 // userdata must live longer than the NativeConvert handle.
 // However, c_struct is a strong reference to each field, so this is not a problem.
-pub unsafe fn get_conv(userdata: &LuaAnyUserData) -> LuaResult<*const dyn NativeConvert> {
-    if userdata.is::<CStruct>() {
-        Ok(userdata.to_pointer().cast::<CStruct>() as *const dyn NativeConvert)
-    } else if userdata.is::<CArr>() {
-        Ok(userdata.to_pointer().cast::<CArr>() as *const dyn NativeConvert)
-    } else if userdata.is::<CPtr>() {
-        Ok(userdata.to_pointer().cast::<CPtr>() as *const dyn NativeConvert)
+pub unsafe fn get_conv(userdata: &LuaAnyUserData) -> LuaResult<*const dyn FfiConvert> {
+    if userdata.is::<CStructInfo>() {
+        Ok(userdata.to_pointer().cast::<CStructInfo>() as *const dyn FfiConvert)
+    } else if userdata.is::<CArrInfo>() {
+        Ok(userdata.to_pointer().cast::<CArrInfo>() as *const dyn FfiConvert)
+    } else if userdata.is::<CPtrInfo>() {
+        Ok(userdata.to_pointer().cast::<CPtrInfo>() as *const dyn FfiConvert)
     } else {
-        c_type_helper::get_conv(userdata)
+        ctype_helper::get_conv(userdata)
         // TODO: struct and more
     }
 }
 
-pub unsafe fn get_conv_list(table: &LuaTable) -> LuaResult<Vec<*const dyn NativeConvert>> {
+pub unsafe fn get_conv_list(table: &LuaTable) -> LuaResult<Vec<*const dyn FfiConvert>> {
     let len: usize = table.raw_len();
-    let mut conv_list = Vec::<*const dyn NativeConvert>::with_capacity(len);
+    let mut conv_list = Vec::<*const dyn FfiConvert>::with_capacity(len);
 
     for i in 0..len {
         let value: LuaValue = table.raw_get(i + 1)?;
@@ -135,27 +135,27 @@ pub unsafe fn get_conv_list(table: &LuaTable) -> LuaResult<Vec<*const dyn Native
 }
 
 pub fn get_size(this: &LuaAnyUserData) -> LuaResult<usize> {
-    if this.is::<CStruct>() {
-        Ok(this.borrow::<CStruct>()?.get_size())
-    } else if this.is::<CArr>() {
-        Ok(this.borrow::<CArr>()?.get_size())
-    } else if this.is::<CPtr>() {
-        Ok(this.borrow::<CPtr>()?.get_size())
+    if this.is::<CStructInfo>() {
+        Ok(this.borrow::<CStructInfo>()?.get_size())
+    } else if this.is::<CArrInfo>() {
+        Ok(this.borrow::<CArrInfo>()?.get_size())
+    } else if this.is::<CPtrInfo>() {
+        Ok(this.borrow::<CPtrInfo>()?.get_size())
     } else {
-        c_type_helper::get_size(this)
+        ctype_helper::get_size(this)
     }
 }
 
 // get libffi_type from any c-type userdata
 pub fn get_middle_type(userdata: &LuaAnyUserData) -> LuaResult<Type> {
-    if userdata.is::<CStruct>() {
-        Ok(userdata.borrow::<CStruct>()?.get_type())
-    } else if let Some(middle_type) = c_type_helper::get_middle_type(userdata)? {
+    if userdata.is::<CStructInfo>() {
+        Ok(userdata.borrow::<CStructInfo>()?.get_type())
+    } else if let Some(middle_type) = ctype_helper::get_middle_type(userdata)? {
         Ok(middle_type)
-    } else if userdata.is::<CArr>() {
-        Ok(userdata.borrow::<CArr>()?.get_type())
-    } else if userdata.is::<CPtr>() {
-        Ok(CPtr::get_type())
+    } else if userdata.is::<CArrInfo>() {
+        Ok(userdata.borrow::<CArrInfo>()?.get_type())
+    } else if userdata.is::<CPtrInfo>() {
+        Ok(CPtrInfo::get_type())
     } else {
         Err(LuaError::external(format!(
             "Unexpected field. CStruct, CType, CString or CArr is required for element but got {}",
@@ -192,15 +192,15 @@ pub fn get_middle_type_list(table: &LuaTable) -> LuaResult<Vec<Type>> {
 
 // stringify any c-type userdata (for recursive)
 pub fn stringify(lua: &Lua, userdata: &LuaAnyUserData) -> LuaResult<String> {
-    if userdata.is::<CStruct>() {
-        CStruct::stringify(lua, userdata)
-    } else if userdata.is::<CArr>() {
-        CArr::stringify(lua, userdata)
-    } else if userdata.is::<CPtr>() {
-        CPtr::stringify(lua, userdata)
-    } else if userdata.is::<CFunc>() {
-        CFunc::stringify(lua, userdata)
-    } else if let Some(name) = c_type_helper::get_name(userdata)? {
+    if userdata.is::<CStructInfo>() {
+        CStructInfo::stringify(lua, userdata)
+    } else if userdata.is::<CArrInfo>() {
+        CArrInfo::stringify(lua, userdata)
+    } else if userdata.is::<CPtrInfo>() {
+        CPtrInfo::stringify(lua, userdata)
+    } else if userdata.is::<CFnInfo>() {
+        CFnInfo::stringify(lua, userdata)
+    } else if let Some(name) = ctype_helper::get_name(userdata)? {
         Ok(String::from(name))
     } else {
         Ok(String::from("unknown"))
@@ -209,15 +209,15 @@ pub fn stringify(lua: &Lua, userdata: &LuaAnyUserData) -> LuaResult<String> {
 
 // get name tag for any c-type userdata
 pub fn get_tag_name(userdata: &LuaAnyUserData) -> LuaResult<String> {
-    Ok(if userdata.is::<CStruct>() {
+    Ok(if userdata.is::<CStructInfo>() {
         String::from("CStruct")
-    } else if userdata.is::<CArr>() {
+    } else if userdata.is::<CArrInfo>() {
         String::from("CArr")
-    } else if userdata.is::<CPtr>() {
+    } else if userdata.is::<CPtrInfo>() {
         String::from("CPtr")
-    } else if userdata.is::<CFunc>() {
+    } else if userdata.is::<CFnInfo>() {
         String::from("CFunc")
-    } else if c_type_helper::is_ctype(userdata) {
+    } else if ctype_helper::is_ctype(userdata) {
         String::from("CType")
     } else {
         String::from("Unknown")
@@ -226,7 +226,7 @@ pub fn get_tag_name(userdata: &LuaAnyUserData) -> LuaResult<String> {
 
 // emulate 'print' for ctype userdata, but ctype is simplified
 pub fn pretty_format(lua: &Lua, userdata: &LuaAnyUserData) -> LuaResult<String> {
-    if c_type_helper::is_ctype(userdata) {
+    if ctype_helper::is_ctype(userdata) {
         stringify(lua, userdata)
     } else {
         Ok(format!(
diff --git a/crates/lune-std-ffi/src/c/mod.rs b/crates/lune-std-ffi/src/c/mod.rs
index 75635f7..075c886 100644
--- a/crates/lune-std-ffi/src/c/mod.rs
+++ b/crates/lune-std-ffi/src/c/mod.rs
@@ -1,20 +1,19 @@
-mod c_arr;
-mod c_func;
-pub mod c_helper;
-mod c_ptr;
-mod c_string;
-mod c_struct;
-mod c_type;
+mod arr_info;
+mod fn_info;
+pub mod helper;
+mod ptr_info;
+mod struct_info;
+mod type_info;
 mod types;
 
 pub use self::{
-    c_arr::CArr,
-    c_func::CFunc,
-    c_helper::method_provider,
-    c_ptr::CPtr,
-    c_struct::CStruct,
-    c_type::{CType, CTypeCast},
-    types::{c_type_helper, export_ctypes},
+    arr_info::CArrInfo,
+    fn_info::CFnInfo,
+    helper::method_provider,
+    ptr_info::CPtrInfo,
+    struct_info::CStructInfo,
+    type_info::{CTypeCast, CTypeInfo},
+    types::{ctype_helper, export_ctypes},
 };
 
 // Named registry table names
diff --git a/crates/lune-std-ffi/src/c/c_ptr.rs b/crates/lune-std-ffi/src/c/ptr_info.rs
similarity index 73%
rename from crates/lune-std-ffi/src/c/c_ptr.rs
rename to crates/lune-std-ffi/src/c/ptr_info.rs
index c56e83b..4383da8 100644
--- a/crates/lune-std-ffi/src/c/c_ptr.rs
+++ b/crates/lune-std-ffi/src/c/ptr_info.rs
@@ -3,41 +3,38 @@ use std::cell::Ref;
 use libffi::middle::Type;
 use mlua::prelude::*;
 
-use super::{association_names::CPTR_INNER, c_helper, c_type_helper, method_provider};
+use super::{association_names::CPTR_INNER, ctype_helper, helper, method_provider};
 use crate::{
-    ffi::{
-        ffi_association::{get_association, set_association},
-        FfiRef, NativeConvert, NativeData, NativeSignedness, NativeSize,
-    },
-    libffi_helper::SIEE_OF_POINTER,
+    data::{FfiConvert, FfiData, FfiSignedness, FfiSize, RefData},
+    ffi::{association, libffi_helper::SIEE_OF_POINTER},
 };
 
-pub struct CPtr {
+pub struct CPtrInfo {
     inner_size: usize,
 }
 
-impl NativeSignedness for CPtr {
+impl FfiSignedness for CPtrInfo {
     fn get_signedness(&self) -> bool {
         false
     }
 }
-impl NativeSize for CPtr {
+impl FfiSize for CPtrInfo {
     fn get_size(&self) -> usize {
         SIEE_OF_POINTER
     }
 }
-impl NativeConvert for CPtr {
+impl FfiConvert for CPtrInfo {
     // Convert luavalue into data, then write into ptr
-    unsafe fn luavalue_into<'lua>(
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         if let LuaValue::UserData(value_userdata) = value {
-            if value_userdata.is::<FfiRef>() {
-                let value_ref = value_userdata.borrow::<FfiRef>()?;
+            if value_userdata.is::<RefData>() {
+                let value_ref = value_userdata.borrow::<RefData>()?;
                 value_ref
                     .check_boundary(0, self.inner_size)
                     .then_some(())
@@ -56,17 +53,17 @@ impl NativeConvert for CPtr {
     }
 
     // Read data from ptr, then convert into luavalue
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         _lua: &'lua Lua,
         _offset: isize,
-        _data_handle: &Ref<dyn NativeData>,
+        _data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
         Err(LuaError::external("Conversion of pointer is not allowed"))
     }
 }
 
-impl CPtr {
+impl CPtrInfo {
     // Create pointer type with '.inner' field
     // inner can be CArr, CType or CStruct
     pub fn from_userdata<'lua>(
@@ -74,10 +71,10 @@ impl CPtr {
         inner: &LuaAnyUserData,
     ) -> LuaResult<LuaAnyUserData<'lua>> {
         let value = lua.create_userdata(Self {
-            inner_size: c_helper::get_size(inner)?,
+            inner_size: helper::get_size(inner)?,
         })?;
 
-        set_association(lua, CPTR_INNER, &value, inner)?;
+        association::set(lua, CPTR_INNER, &value, inner)?;
 
         Ok(value)
     }
@@ -85,8 +82,8 @@ impl CPtr {
     // Stringify CPtr with inner ctype
     pub fn stringify(lua: &Lua, userdata: &LuaAnyUserData) -> LuaResult<String> {
         if let LuaValue::UserData(inner_userdata) = userdata.get("inner")? {
-            let pretty_formatted = c_helper::pretty_format(lua, &inner_userdata)?;
-            Ok(if c_type_helper::is_ctype(&inner_userdata) {
+            let pretty_formatted = helper::pretty_format(lua, &inner_userdata)?;
+            Ok(if ctype_helper::is_ctype(&inner_userdata) {
                 pretty_formatted
             } else {
                 format!(" {pretty_formatted} ")
@@ -102,11 +99,11 @@ impl CPtr {
     }
 }
 
-impl LuaUserData for CPtr {
+impl LuaUserData for CPtrInfo {
     fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
         fields.add_field_method_get("size", |_, _| Ok(size_of::<usize>()));
         fields.add_field_function_get("inner", |lua, this| {
-            let inner = get_association(lua, CPTR_INNER, this)?
+            let inner = association::get(lua, CPTR_INNER, this)?
                 .ok_or_else(|| LuaError::external("inner type not found"))?;
             Ok(inner)
         });
diff --git a/crates/lune-std-ffi/src/c/c_struct.rs b/crates/lune-std-ffi/src/c/struct_info.rs
similarity index 76%
rename from crates/lune-std-ffi/src/c/c_struct.rs
rename to crates/lune-std-ffi/src/c/struct_info.rs
index b0042e9..dd3d55f 100644
--- a/crates/lune-std-ffi/src/c/c_struct.rs
+++ b/crates/lune-std-ffi/src/c/struct_info.rs
@@ -3,24 +3,21 @@ use std::{cell::Ref, vec::Vec};
 use libffi::{low, middle::Type, raw};
 use mlua::prelude::*;
 
-use super::{association_names::CSTRUCT_INNER, c_helper, method_provider};
-use crate::ffi::{
-    ffi_association::{get_association, set_association},
-    NativeConvert, NativeData, NativeSignedness, NativeSize, FFI_STATUS_NAMES,
+use super::{association_names::CSTRUCT_INNER, helper, method_provider};
+use crate::{
+    data::{FfiConvert, FfiData, FfiSignedness, FfiSize},
+    ffi::{association, libffi_helper::FFI_STATUS_NAMES},
 };
 
-pub struct CStruct {
+pub struct CStructInfo {
     middle_type: Type,
     size: usize,
     inner_offset_list: Vec<usize>,
-    inner_conv_list: Vec<*const dyn NativeConvert>,
+    inner_conv_list: Vec<*const dyn FfiConvert>,
 }
 
-impl CStruct {
-    pub fn new(
-        fields: Vec<Type>,
-        inner_conv_list: Vec<*const dyn NativeConvert>,
-    ) -> LuaResult<Self> {
+impl CStructInfo {
+    pub fn new(fields: Vec<Type>, inner_conv_list: Vec<*const dyn FfiConvert>) -> LuaResult<Self> {
         let len = fields.len();
         let mut inner_offset_list = Vec::<usize>::with_capacity(len);
         let middle_type = Type::structure(fields);
@@ -60,32 +57,33 @@ impl CStruct {
         lua: &'lua Lua,
         table: LuaTable<'lua>,
     ) -> LuaResult<LuaAnyUserData<'lua>> {
-        let cstruct = lua.create_userdata(Self::new(
-            c_helper::get_middle_type_list(&table)?,
-            unsafe { c_helper::get_conv_list(&table)? },
-        )?)?;
+        let cstruct = lua
+            .create_userdata(Self::new(helper::get_middle_type_list(&table)?, unsafe {
+                helper::get_conv_list(&table)?
+            })?)?;
 
         table.set_readonly(true);
-        set_association(lua, CSTRUCT_INNER, &cstruct, table)?;
+        association::set(lua, CSTRUCT_INNER, &cstruct, table)?;
         Ok(cstruct)
     }
 
     // Stringify cstruct for pretty printing like:
     // <CStruct( u8, i32, size = 8 )>
     pub fn stringify(lua: &Lua, userdata: &LuaAnyUserData) -> LuaResult<String> {
-        if let LuaValue::Table(fields) = get_association(lua, CSTRUCT_INNER, userdata)?
+        if let LuaValue::Table(fields) = association::get(lua, CSTRUCT_INNER, userdata)?
             .ok_or_else(|| LuaError::external("Field table not found"))?
         {
             let mut result = String::from(" ");
             for i in 0..fields.raw_len() {
                 let child: LuaAnyUserData = fields.raw_get(i + 1)?;
-                let pretty_formatted = c_helper::pretty_format(lua, &child)?;
+                let pretty_formatted = helper::pretty_format(lua, &child)?;
                 result.push_str(format!("{pretty_formatted}, ").as_str());
             }
 
             // size of
-            result
-                .push_str(format!("size = {} ", userdata.borrow::<CStruct>()?.get_size()).as_str());
+            result.push_str(
+                format!("size = {} ", userdata.borrow::<CStructInfo>()?.get_size()).as_str(),
+            );
             Ok(result)
         } else {
             Err(LuaError::external("failed to get inner type table."))
@@ -107,23 +105,23 @@ impl CStruct {
     }
 }
 
-impl NativeSize for CStruct {
+impl FfiSize for CStructInfo {
     fn get_size(&self) -> usize {
         self.size
     }
 }
-impl NativeSignedness for CStruct {
+impl FfiSignedness for CStructInfo {
     fn get_signedness(&self) -> bool {
         false
     }
 }
-impl NativeConvert for CStruct {
+impl FfiConvert for CStructInfo {
     // FIXME: FfiBox, FfiRef support required
-    unsafe fn luavalue_into<'lua>(
+    unsafe fn value_into_data<'lua>(
         &self,
         lua: &'lua Lua,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let LuaValue::Table(ref table) = value else {
@@ -133,18 +131,21 @@ impl NativeConvert for CStruct {
             let field_offset = self.offset(i)? as isize;
             let data: LuaValue = table.get(i + 1)?;
 
-            conv.as_ref()
-                .unwrap()
-                .luavalue_into(lua, field_offset + offset, data_handle, data)?;
+            conv.as_ref().unwrap().value_into_data(
+                lua,
+                field_offset + offset,
+                data_handle,
+                data,
+            )?;
         }
         Ok(())
     }
 
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
         let table = lua.create_table_with_capacity(self.inner_conv_list.len(), 0)?;
         for (i, conv) in self.inner_conv_list.iter().enumerate() {
@@ -153,14 +154,14 @@ impl NativeConvert for CStruct {
                 i + 1,
                 conv.as_ref()
                     .unwrap()
-                    .luavalue_from(lua, field_offset + offset, data_handle)?,
+                    .value_from_data(lua, field_offset + offset, data_handle)?,
             )?;
         }
         Ok(LuaValue::Table(table))
     }
 }
 
-impl LuaUserData for CStruct {
+impl LuaUserData for CStructInfo {
     fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
         fields.add_field_method_get("size", |_, this| Ok(this.get_size()));
     }
@@ -184,7 +185,7 @@ impl LuaUserData for CStruct {
         // Simply pass type in the locked table used when first creating this object.
         // By referencing the table to struct, the types inside do not disappear
         methods.add_function("field", |lua, (this, field): (LuaAnyUserData, usize)| {
-            if let LuaValue::Table(fields) = get_association(lua, CSTRUCT_INNER, this)?
+            if let LuaValue::Table(fields) = association::get(lua, CSTRUCT_INNER, this)?
                 .ok_or_else(|| LuaError::external("Field table not found"))?
             {
                 let value: LuaValue = fields.raw_get(field + 1)?;
diff --git a/crates/lune-std-ffi/src/c/c_type.rs b/crates/lune-std-ffi/src/c/type_info.rs
similarity index 86%
rename from crates/lune-std-ffi/src/c/c_type.rs
rename to crates/lune-std-ffi/src/c/type_info.rs
index c90f195..dd459e8 100644
--- a/crates/lune-std-ffi/src/c/c_type.rs
+++ b/crates/lune-std-ffi/src/c/type_info.rs
@@ -6,10 +6,10 @@ use libffi::middle::Type;
 use lune_utils::fmt::{pretty_format_value, ValueFormatConfig};
 use mlua::prelude::*;
 
+use super::method_provider;
 use crate::{
-    c::method_provider,
-    ffi::{GetNativeData, NativeConvert, NativeData, NativeSignedness, NativeSize},
-    libffi_helper::get_ensured_size,
+    data::{FfiConvert, FfiData, FfiSignedness, FfiSize, GetFfiData},
+    ffi::libffi_helper::get_ensured_size,
 };
 
 // Cast native data
@@ -19,8 +19,8 @@ pub trait CTypeCast {
         &self,
         from_ctype: &LuaAnyUserData,
         into_ctype: &LuaAnyUserData,
-        _from: &Ref<dyn NativeData>,
-        _into: &Ref<dyn NativeData>,
+        _from: &Ref<dyn FfiData>,
+        _into: &Ref<dyn FfiData>,
     ) -> LuaResult<()> {
         // Show error if have no cast implement
         Err(Self::cast_failed_with(self, from_ctype, into_ctype))
@@ -40,23 +40,23 @@ pub trait CTypeCast {
     }
 }
 
-pub struct CType<T> {
+pub struct CTypeInfo<T> {
     middle_type: Type,
     size: usize,
     name: &'static str,
     _phantom: PhantomData<T>,
 }
 
-impl<T> NativeSize for CType<T> {
+impl<T> FfiSize for CTypeInfo<T> {
     fn get_size(&self) -> usize {
         self.size
     }
 }
 
-impl<T> CType<T>
+impl<T> CTypeInfo<T>
 where
     T: 'static,
-    Self: CTypeCast + NativeSignedness + NativeConvert + NativeSize,
+    Self: CTypeCast + FfiSignedness + FfiConvert + FfiSize,
 {
     pub fn new_with_libffi_type<'lua>(
         lua: &'lua Lua,
@@ -85,10 +85,10 @@ where
     }
 }
 
-impl<T> LuaUserData for CType<T>
+impl<T> LuaUserData for CTypeInfo<T>
 where
     T: 'static,
-    Self: CTypeCast + NativeSignedness + NativeConvert + NativeSize,
+    Self: CTypeCast + FfiSignedness + FfiConvert + FfiSize,
 {
     fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
         fields.add_field_method_get("size", |_, this| Ok(this.get_size()));
diff --git a/crates/lune-std-ffi/src/c/types/f32.rs b/crates/lune-std-ffi/src/c/types/f32.rs
index 8dc8645..f397433 100644
--- a/crates/lune-std-ffi/src/c/types/f32.rs
+++ b/crates/lune-std-ffi/src/c/types/f32.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<f32> {
+impl FfiSignedness for CTypeInfo<f32> {
     fn get_signedness(&self) -> bool {
         true
     }
 }
 
-impl NativeConvert for CType<f32> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<f32> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: f32 = match value {
@@ -40,12 +42,12 @@ impl NativeConvert for CType<f32> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
         let value = unsafe {
             (*data_handle.get_pointer().byte_offset(offset).cast::<f32>()).into_lua(lua)?
diff --git a/crates/lune-std-ffi/src/c/types/f64.rs b/crates/lune-std-ffi/src/c/types/f64.rs
index 16c3a20..1055c5c 100644
--- a/crates/lune-std-ffi/src/c/types/f64.rs
+++ b/crates/lune-std-ffi/src/c/types/f64.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<f64> {
+impl FfiSignedness for CTypeInfo<f64> {
     fn get_signedness(&self) -> bool {
         true
     }
 }
 
-impl NativeConvert for CType<f64> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<f64> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: f64 = match value {
@@ -40,12 +42,12 @@ impl NativeConvert for CType<f64> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
         let value = unsafe {
             (*data_handle.get_pointer().byte_offset(offset).cast::<f64>()).into_lua(lua)?
diff --git a/crates/lune-std-ffi/src/c/types/i128.rs b/crates/lune-std-ffi/src/c/types/i128.rs
index d4784e8..6a0b55c 100644
--- a/crates/lune-std-ffi/src/c/types/i128.rs
+++ b/crates/lune-std-ffi/src/c/types/i128.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<i128> {
+impl FfiSignedness for CTypeInfo<i128> {
     fn get_signedness(&self) -> bool {
         true
     }
 }
 
-impl NativeConvert for CType<i128> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<i128> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: i128 = match value {
@@ -40,14 +42,16 @@ impl NativeConvert for CType<i128> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<i128>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle.get_pointer().byte_offset(offset).cast::<i128>()).into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/i16.rs b/crates/lune-std-ffi/src/c/types/i16.rs
index 47e3391..a6c2948 100644
--- a/crates/lune-std-ffi/src/c/types/i16.rs
+++ b/crates/lune-std-ffi/src/c/types/i16.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<i16> {
+impl FfiSignedness for CTypeInfo<i16> {
     fn get_signedness(&self) -> bool {
         true
     }
 }
 
-impl NativeConvert for CType<i16> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<i16> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: i16 = match value {
@@ -40,14 +42,16 @@ impl NativeConvert for CType<i16> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<i16>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle.get_pointer().byte_offset(offset).cast::<i16>()).into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/i32.rs b/crates/lune-std-ffi/src/c/types/i32.rs
index 088f948..8afd129 100644
--- a/crates/lune-std-ffi/src/c/types/i32.rs
+++ b/crates/lune-std-ffi/src/c/types/i32.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<i32> {
+impl FfiSignedness for CTypeInfo<i32> {
     fn get_signedness(&self) -> bool {
         true
     }
 }
 
-impl NativeConvert for CType<i32> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<i32> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: i32 = match value {
@@ -40,14 +42,16 @@ impl NativeConvert for CType<i32> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<i32>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle.get_pointer().byte_offset(offset).cast::<i32>()).into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/i64.rs b/crates/lune-std-ffi/src/c/types/i64.rs
index 4ea87c6..f4f914f 100644
--- a/crates/lune-std-ffi/src/c/types/i64.rs
+++ b/crates/lune-std-ffi/src/c/types/i64.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<i64> {
+impl FfiSignedness for CTypeInfo<i64> {
     fn get_signedness(&self) -> bool {
         true
     }
 }
 
-impl NativeConvert for CType<i64> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<i64> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: i64 = match value {
@@ -40,14 +42,16 @@ impl NativeConvert for CType<i64> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<i64>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle.get_pointer().byte_offset(offset).cast::<i64>()).into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/i8.rs b/crates/lune-std-ffi/src/c/types/i8.rs
index 083f1fc..53ec853 100644
--- a/crates/lune-std-ffi/src/c/types/i8.rs
+++ b/crates/lune-std-ffi/src/c/types/i8.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<i8> {
+impl FfiSignedness for CTypeInfo<i8> {
     fn get_signedness(&self) -> bool {
         true
     }
 }
 
-impl NativeConvert for CType<i8> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<i8> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: i8 = match value {
@@ -36,14 +38,15 @@ impl NativeConvert for CType<i8> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<i8>()).into_lua(lua)? };
+        let value =
+            unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<i8>()).into_lua(lua)? };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/isize.rs b/crates/lune-std-ffi/src/c/types/isize.rs
index 261d217..ccd5405 100644
--- a/crates/lune-std-ffi/src/c/types/isize.rs
+++ b/crates/lune-std-ffi/src/c/types/isize.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<isize> {
+impl FfiSignedness for CTypeInfo<isize> {
     fn get_signedness(&self) -> bool {
         true
     }
 }
 
-impl NativeConvert for CType<isize> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<isize> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: isize = match value {
@@ -36,18 +38,27 @@ impl NativeConvert for CType<isize> {
             }
         };
         unsafe {
-            *(data_handle.get_pointer().byte_offset(offset).cast::<isize>()) = value;
+            *(data_handle
+                .get_pointer()
+                .byte_offset(offset)
+                .cast::<isize>()) = value;
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<isize>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle
+                .get_pointer()
+                .byte_offset(offset)
+                .cast::<isize>())
+            .into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/mod.rs b/crates/lune-std-ffi/src/c/types/mod.rs
index 8c8840a..0e0387e 100644
--- a/crates/lune-std-ffi/src/c/types/mod.rs
+++ b/crates/lune-std-ffi/src/c/types/mod.rs
@@ -7,8 +7,8 @@ use libffi::middle::Type;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::{CType, CTypeCast};
-use crate::ffi::{native_num_cast, NativeConvert, NativeData, NativeSize};
+use super::{CTypeCast, CTypeInfo};
+use crate::data::{num_cast, FfiConvert, FfiData, FfiSize};
 
 pub mod f32;
 pub mod f64;
@@ -30,7 +30,7 @@ macro_rules! create_ctypes {
     ($lua:ident, $(( $name:expr, $rust_type:ty, $libffi_type:expr ),)* ) => {
         Ok(vec![$((
             $name,
-            CType::<$rust_type>::new_with_libffi_type($lua, $libffi_type, $name)?,
+            CTypeInfo::<$rust_type>::new_with_libffi_type($lua, $libffi_type, $name)?,
         ),)*])
     };
 }
@@ -80,14 +80,14 @@ pub fn export_ctypes(lua: &Lua) -> LuaResult<Vec<(&'static str, LuaAnyUserData)>
 // Implement type-casting for numeric ctypes
 macro_rules! define_cast_num {
     ($from_rust_type:ident, $self:ident, $from_ctype:ident, $into_ctype:ident, $from:ident, $into:ident, $($into_rust_type:ty)*) => {
-        $( if $into_ctype.is::<CType<$into_rust_type>>() {
-            native_num_cast::<$from_rust_type, $into_rust_type>($from, $into)
+        $( if $into_ctype.is::<CTypeInfo<$into_rust_type>>() {
+            num_cast::<$from_rust_type, $into_rust_type>($from, $into)
         } else )* {
             Err($self.cast_failed_with($from_ctype, $into_ctype))
         }
     };
 }
-impl<From> CTypeCast for CType<From>
+impl<From> CTypeCast for CTypeInfo<From>
 where
     From: AsPrimitive<u8>
         + AsPrimitive<u16>
@@ -106,41 +106,41 @@ where
 {
     fn cast(
         &self,
-        from_ctype: &LuaAnyUserData,
-        into_ctype: &LuaAnyUserData,
-        from: &Ref<dyn NativeData>,
-        into: &Ref<dyn NativeData>,
+        from_info: &LuaAnyUserData,
+        into_info: &LuaAnyUserData,
+        from: &Ref<dyn FfiData>,
+        into: &Ref<dyn FfiData>,
     ) -> LuaResult<()> {
         define_cast_num!(
-            From, self, into_ctype, from_ctype, from, into,
+            From, self, into_info, from_info, from, into,
             u8 u16 u32 u64 u128 i8 i16 i32 i64 i128 f32 f64 usize isize
         )
     }
 }
 
-pub mod c_type_helper {
+pub mod ctype_helper {
     use super::*;
 
     // To prevent drop NativeConvert, we must use ffi_association to ensure children keep alive
     macro_rules! define_get_conv {
         ($userdata:ident, $( $rust_type:ty )*) => {
-            $( if $userdata.is::<CType<$rust_type>>() {
-                Ok($userdata.to_pointer().cast::<CType<$rust_type>>() as *const dyn NativeConvert)
+            $( if $userdata.is::<CTypeInfo<$rust_type>>() {
+                Ok($userdata.to_pointer().cast::<CTypeInfo<$rust_type>>() as *const dyn FfiConvert)
             } else )* {
                 Err(LuaError::external("Unexpected type"))
             }
         };
     }
     #[inline]
-    pub fn get_conv(userdata: &LuaAnyUserData) -> LuaResult<*const dyn NativeConvert> {
+    pub fn get_conv(userdata: &LuaAnyUserData) -> LuaResult<*const dyn FfiConvert> {
         define_get_conv!(userdata, u8 u16 u32 u64 u128 i8 i16 i32 i64 i128 f32 f64 usize isize)
     }
 
     // Get size of ctype (not includes struct, arr, ... only CType<*>)
     macro_rules! define_get_size {
         ($userdata:ident, $( $rust_type:ty )*) => {
-            $( if $userdata.is::<CType<$rust_type>>() {
-                Ok($userdata.borrow::<CType<$rust_type>>()?.get_size())
+            $( if $userdata.is::<CTypeInfo<$rust_type>>() {
+                Ok($userdata.borrow::<CTypeInfo<$rust_type>>()?.get_size())
             } else )* {
                 Err(LuaError::external("Unexpected type"))
             }
@@ -154,8 +154,8 @@ pub mod c_type_helper {
     // Get name of ctype
     macro_rules! define_get_name {
         ($userdata:ident, $( $rust_type:ty )*) => {
-            $( if $userdata.is::<CType<$rust_type>>() {
-                Ok(Some($userdata.borrow::<CType<$rust_type>>()?.get_name()))
+            $( if $userdata.is::<CTypeInfo<$rust_type>>() {
+                Ok(Some($userdata.borrow::<CTypeInfo<$rust_type>>()?.get_name()))
             } else )* {
                 Ok(None)
             }
@@ -169,8 +169,8 @@ pub mod c_type_helper {
     // Get libffi_type of ctype
     macro_rules! define_get_middle_type {
         ($userdata:ident, $( $rust_type:ty )*) => {
-            $( if $userdata.is::<CType<$rust_type>>() {
-                Ok(Some($userdata.borrow::<CType<$rust_type>>()?.get_type()))
+            $( if $userdata.is::<CTypeInfo<$rust_type>>() {
+                Ok(Some($userdata.borrow::<CTypeInfo<$rust_type>>()?.get_type()))
             } else )* {
                 Ok(None)
             }
@@ -183,7 +183,7 @@ pub mod c_type_helper {
 
     macro_rules! define_is_ctype {
         ($userdata:ident, $( $rust_type:ty )*) => {
-            $( if $userdata.is::<CType<$rust_type>>() {
+            $( if $userdata.is::<CTypeInfo<$rust_type>>() {
                 true
             } else )* {
                 false
diff --git a/crates/lune-std-ffi/src/c/types/u128.rs b/crates/lune-std-ffi/src/c/types/u128.rs
index f68d91f..34af1e5 100644
--- a/crates/lune-std-ffi/src/c/types/u128.rs
+++ b/crates/lune-std-ffi/src/c/types/u128.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<u128> {
+impl FfiSignedness for CTypeInfo<u128> {
     fn get_signedness(&self) -> bool {
         false
     }
 }
 
-impl NativeConvert for CType<u128> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<u128> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: u128 = match value {
@@ -40,14 +42,16 @@ impl NativeConvert for CType<u128> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<u128>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle.get_pointer().byte_offset(offset).cast::<u128>()).into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/u16.rs b/crates/lune-std-ffi/src/c/types/u16.rs
index b29d4da..b342834 100644
--- a/crates/lune-std-ffi/src/c/types/u16.rs
+++ b/crates/lune-std-ffi/src/c/types/u16.rs
@@ -3,23 +3,25 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<u16> {
+impl FfiSignedness for CTypeInfo<u16> {
     fn get_signedness(&self) -> bool {
         false
     }
 }
 
-impl NativeConvert for CType<u16> {
+impl FfiConvert for CTypeInfo<u16> {
     // Convert luavalue into data, then write into ptr
-    unsafe fn luavalue_into<'lua>(
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: u16 = match value {
@@ -41,14 +43,16 @@ impl NativeConvert for CType<u16> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<u16>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle.get_pointer().byte_offset(offset).cast::<u16>()).into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/u32.rs b/crates/lune-std-ffi/src/c/types/u32.rs
index 798f586..09d9a07 100644
--- a/crates/lune-std-ffi/src/c/types/u32.rs
+++ b/crates/lune-std-ffi/src/c/types/u32.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<u32> {
+impl FfiSignedness for CTypeInfo<u32> {
     fn get_signedness(&self) -> bool {
         false
     }
 }
 
-impl NativeConvert for CType<u32> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<u32> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: u32 = match value {
@@ -40,14 +42,16 @@ impl NativeConvert for CType<u32> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<u32>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle.get_pointer().byte_offset(offset).cast::<u32>()).into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/u64.rs b/crates/lune-std-ffi/src/c/types/u64.rs
index 757ece7..beb1ba4 100644
--- a/crates/lune-std-ffi/src/c/types/u64.rs
+++ b/crates/lune-std-ffi/src/c/types/u64.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<u64> {
+impl FfiSignedness for CTypeInfo<u64> {
     fn get_signedness(&self) -> bool {
         false
     }
 }
 
-impl NativeConvert for CType<u64> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<u64> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: u64 = match value {
@@ -40,14 +42,16 @@ impl NativeConvert for CType<u64> {
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<u64>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle.get_pointer().byte_offset(offset).cast::<u64>()).into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/types/u8.rs b/crates/lune-std-ffi/src/c/types/u8.rs
index 273e876..a7d9ad3 100644
--- a/crates/lune-std-ffi/src/c/types/u8.rs
+++ b/crates/lune-std-ffi/src/c/types/u8.rs
@@ -3,23 +3,25 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<u8> {
+impl FfiSignedness for CTypeInfo<u8> {
     fn get_signedness(&self) -> bool {
         false
     }
 }
 
-impl NativeConvert for CType<u8> {
+impl FfiConvert for CTypeInfo<u8> {
     // Convert luavalue into data, then write into ptr
-    unsafe fn luavalue_into<'lua>(
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: u8 = match value {
@@ -39,12 +41,12 @@ impl NativeConvert for CType<u8> {
     }
 
     // Read data from ptr, then convert into luavalue
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
         let value =
             unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<u8>()).into_lua(lua)? };
diff --git a/crates/lune-std-ffi/src/c/types/usize.rs b/crates/lune-std-ffi/src/c/types/usize.rs
index 0dc7afc..0fa4442 100644
--- a/crates/lune-std-ffi/src/c/types/usize.rs
+++ b/crates/lune-std-ffi/src/c/types/usize.rs
@@ -3,22 +3,24 @@ use std::cell::Ref;
 use mlua::prelude::*;
 use num::cast::AsPrimitive;
 
-use super::super::c_type::CType;
-use crate::ffi::{NativeConvert, NativeData, NativeSignedness};
+use crate::{
+    c::type_info::CTypeInfo,
+    data::{FfiConvert, FfiData, FfiSignedness},
+};
 
-impl NativeSignedness for CType<usize> {
+impl FfiSignedness for CTypeInfo<usize> {
     fn get_signedness(&self) -> bool {
         false
     }
 }
 
-impl NativeConvert for CType<usize> {
-    unsafe fn luavalue_into<'lua>(
+impl FfiConvert for CTypeInfo<usize> {
+    unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
         let value: usize = match value {
@@ -36,18 +38,27 @@ impl NativeConvert for CType<usize> {
             }
         };
         unsafe {
-            *(data_handle.get_pointer().byte_offset(offset).cast::<usize>()) = value;
+            *(data_handle
+                .get_pointer()
+                .byte_offset(offset)
+                .cast::<usize>()) = value;
         }
         Ok(())
     }
-    unsafe fn luavalue_from<'lua>(
+    unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         // _type_userdata: &LuaAnyUserData<'lua>,
         offset: isize,
-        data_handle: &Ref<dyn NativeData>,
+        data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        let value = unsafe { (*data_handle.get_pointer().byte_offset(offset).cast::<usize>()).into_lua(lua)? };
+        let value = unsafe {
+            (*data_handle
+                .get_pointer()
+                .byte_offset(offset)
+                .cast::<usize>())
+            .into_lua(lua)?
+        };
         Ok(value)
     }
 }
diff --git a/crates/lune-std-ffi/src/c/c_void.rs b/crates/lune-std-ffi/src/c/void_info.rs
similarity index 100%
rename from crates/lune-std-ffi/src/c/c_void.rs
rename to crates/lune-std-ffi/src/c/void_info.rs
diff --git a/crates/lune-std-ffi/src/ffi/ffi_box/flag.rs b/crates/lune-std-ffi/src/data/box_data/flag.rs
similarity index 64%
rename from crates/lune-std-ffi/src/ffi/ffi_box/flag.rs
rename to crates/lune-std-ffi/src/data/box_data/flag.rs
index dfb4757..f54a1b5 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_box/flag.rs
+++ b/crates/lune-std-ffi/src/data/box_data/flag.rs
@@ -1,10 +1,10 @@
-use super::super::bit_mask::*;
+use crate::ffi::bit_mask::*;
 
-pub enum FfiBoxFlag {
+pub enum BoxDataFlag {
     Leaked,
 }
 
-impl FfiBoxFlag {
+impl BoxDataFlag {
     pub const fn value(&self) -> u8 {
         match self {
             Self::Leaked => U8_MASK2,
diff --git a/crates/lune-std-ffi/src/ffi/ffi_box/mod.rs b/crates/lune-std-ffi/src/data/box_data/mod.rs
similarity index 79%
rename from crates/lune-std-ffi/src/ffi/ffi_box/mod.rs
rename to crates/lune-std-ffi/src/data/box_data/mod.rs
index b10b5e3..ea5b1f4 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_box/mod.rs
+++ b/crates/lune-std-ffi/src/data/box_data/mod.rs
@@ -2,21 +2,18 @@ use std::{alloc, alloc::Layout, boxed::Box, mem::ManuallyDrop, ptr};
 
 use mlua::prelude::*;
 
-use super::{
-    association_names::REF_INNER,
-    bit_mask::*,
-    ffi_association::set_association,
-    ffi_ref::{FfiRef, FfiRefBounds, FfiRefFlag},
-    NativeData,
+use crate::{
+    data::{association_names::REF_INNER, RefData, RefDataBounds, RefDataFlag},
+    ffi::{association, bit_mask::*, FfiData},
 };
 
 mod flag;
 
-pub use self::flag::FfiBoxFlag;
+pub use self::flag::BoxDataFlag;
 
 // Ref which created by lua should not be dereferenceable,
 const BOX_REF_FLAGS: u8 =
-    FfiRefFlag::Readable.value() | FfiRefFlag::Writable.value() | FfiRefFlag::Offsetable.value();
+    RefDataFlag::Readable.value() | RefDataFlag::Writable.value() | RefDataFlag::Offsetable.value();
 
 // It is an untyped, sized memory area that Lua can manage.
 // This area is safe within Lua. Operations have their boundaries checked.
@@ -27,14 +24,14 @@ const BOX_REF_FLAGS: u8 =
 // rather, it creates more heap space, so it should be used appropriately
 // where necessary.
 
-pub struct FfiBox {
+pub struct BoxData {
     flags: u8,
     data: ManuallyDrop<Box<[u8]>>,
 }
 
 const FFI_BOX_PRINT_MAX_LENGTH: usize = 1024;
 
-impl FfiBox {
+impl BoxData {
     // For efficiency, it is initialized non-zeroed.
     pub fn new(size: usize) -> Self {
         let slice = unsafe {
@@ -66,7 +63,7 @@ impl FfiBox {
     }
 
     pub fn leak(&mut self) {
-        self.flags = u8_set(self.flags, FfiBoxFlag::Leaked.value(), true);
+        self.flags = u8_set(self.flags, BoxDataFlag::Leaked.value(), true);
     }
 
     // Make FfiRef from box, with boundary checking
@@ -75,8 +72,8 @@ impl FfiBox {
         this: LuaAnyUserData<'lua>,
         offset: Option<isize>,
     ) -> LuaResult<LuaAnyUserData<'lua>> {
-        let target = this.borrow::<FfiBox>()?;
-        let mut bounds = FfiRefBounds::new(0, target.size());
+        let target = this.borrow::<BoxData>()?;
+        let mut bounds = RefDataBounds::new(0, target.size());
         let mut ptr = unsafe { target.get_pointer() };
 
         // Calculate offset
@@ -92,10 +89,10 @@ impl FfiBox {
             bounds = bounds.offset(t);
         }
 
-        let luaref = lua.create_userdata(FfiRef::new(ptr.cast(), BOX_REF_FLAGS, bounds))?;
+        let luaref = lua.create_userdata(RefData::new(ptr.cast(), BOX_REF_FLAGS, bounds))?;
 
         // Makes box alive longer then ref
-        set_association(lua, REF_INNER, &luaref, &this)?;
+        association::set(lua, REF_INNER, &luaref, &this)?;
 
         Ok(luaref)
     }
@@ -115,15 +112,15 @@ impl FfiBox {
     }
 }
 
-impl Drop for FfiBox {
+impl Drop for BoxData {
     fn drop(&mut self) {
-        if u8_test_not(self.flags, FfiBoxFlag::Leaked.value()) {
+        if u8_test_not(self.flags, BoxDataFlag::Leaked.value()) {
             unsafe { self.drop() };
         }
     }
 }
 
-impl NativeData for FfiBox {
+impl FfiData for BoxData {
     fn check_boundary(&self, offset: isize, size: usize) -> bool {
         if offset < 0 {
             return false;
@@ -141,27 +138,27 @@ impl NativeData for FfiBox {
     }
 }
 
-impl LuaUserData for FfiBox {
+impl LuaUserData for BoxData {
     fn add_fields<'lua, F: LuaUserDataFields<'lua, Self>>(fields: &mut F) {
         fields.add_field_method_get("size", |_, this| Ok(this.size()));
     }
     fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
         // For convenience, :zero returns self.
         methods.add_function_mut("zero", |_, this: LuaAnyUserData| {
-            this.borrow_mut::<FfiBox>()?.zero();
+            this.borrow_mut::<BoxData>()?.zero();
             Ok(this)
         });
         methods.add_function_mut(
             "leak",
             |lua, (this, offset): (LuaAnyUserData, Option<isize>)| {
-                this.borrow_mut::<FfiBox>()?.leak();
-                FfiBox::luaref(lua, this, offset)
+                this.borrow_mut::<BoxData>()?.leak();
+                BoxData::luaref(lua, this, offset)
             },
         );
         methods.add_function(
             "ref",
             |lua, (this, offset): (LuaAnyUserData, Option<isize>)| {
-                FfiBox::luaref(lua, this, offset)
+                BoxData::luaref(lua, this, offset)
             },
         );
         methods.add_meta_method(LuaMetaMethod::ToString, |_, this, ()| Ok(this.stringify()));
diff --git a/crates/lune-std-ffi/src/ffi/ffi_callable.rs b/crates/lune-std-ffi/src/data/callable_data.rs
similarity index 84%
rename from crates/lune-std-ffi/src/ffi/ffi_callable.rs
rename to crates/lune-std-ffi/src/data/callable_data.rs
index b5e4c1d..ca8f65c 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_callable.rs
+++ b/crates/lune-std-ffi/src/data/callable_data.rs
@@ -7,20 +7,20 @@ use libffi::{
 };
 use mlua::prelude::*;
 
-use super::{GetNativeData, NativeArgInfo, NativeData, NativeResultInfo};
+use super::{FfiArgInfo, FfiData, FfiResultInfo, GetFfiData};
 
-pub struct FfiCallable {
+pub struct CallableData {
     cif: *mut ffi_cif,
-    arg_info_list: *const Vec<NativeArgInfo>,
-    result_info: *const NativeResultInfo,
+    arg_info_list: *const Vec<FfiArgInfo>,
+    result_info: *const FfiResultInfo,
     code: CodePtr,
 }
 
-impl FfiCallable {
+impl CallableData {
     pub unsafe fn new(
         cif: *mut ffi_cif,
-        arg_info_list: *const Vec<NativeArgInfo>,
-        result_info: *const NativeResultInfo,
+        arg_info_list: *const Vec<FfiArgInfo>,
+        result_info: *const FfiResultInfo,
         function_pointer: *const (),
     ) -> Self {
         Self {
@@ -33,7 +33,7 @@ impl FfiCallable {
 
     // TODO? async call: if have no lua closure in arguments, fficallble can be called with async way
 
-    pub unsafe fn call(&self, result: &Ref<dyn NativeData>, args: LuaMultiValue) -> LuaResult<()> {
+    pub unsafe fn call(&self, result: &Ref<dyn FfiData>, args: LuaMultiValue) -> LuaResult<()> {
         result
             .check_boundary(0, self.result_info.as_ref().unwrap().size)
             .then_some(())
@@ -74,11 +74,11 @@ impl FfiCallable {
     }
 }
 
-impl LuaUserData for FfiCallable {
+impl LuaUserData for CallableData {
     fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
         methods.add_method(
             "call",
-            |_lua, this: &FfiCallable, mut args: LuaMultiValue| {
+            |_lua, this: &CallableData, mut args: LuaMultiValue| {
                 let result_userdata = args.pop_front().ok_or_else(|| {
                     LuaError::external("first argument must be result data handle")
                 })?;
diff --git a/crates/lune-std-ffi/src/ffi/ffi_closure.rs b/crates/lune-std-ffi/src/data/closure_data.rs
similarity index 78%
rename from crates/lune-std-ffi/src/ffi/ffi_closure.rs
rename to crates/lune-std-ffi/src/data/closure_data.rs
index 7afca46..8175be3 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_closure.rs
+++ b/crates/lune-std-ffi/src/data/closure_data.rs
@@ -8,17 +8,18 @@ use libffi::{
 use mlua::prelude::*;
 
 use super::{
-    ffi_ref::{FfiRefBounds, FfiRefFlag},
-    FfiRef, FFI_STATUS_NAMES,
+    ref_data::{RefDataBounds, RefDataFlag},
+    RefData,
 };
+use crate::ffi::libffi_helper::FFI_STATUS_NAMES;
 
-pub struct FfiClosure<'a> {
+pub struct ClosureData<'a> {
     closure: *mut ffi_closure,
     code: CodePtr,
     userdata: CallbackUserdata<'a>,
 }
 
-impl<'a> Drop for FfiClosure<'a> {
+impl<'a> Drop for ClosureData<'a> {
     fn drop(&mut self) {
         unsafe {
             closure_free(self.closure);
@@ -35,7 +36,7 @@ pub struct CallbackUserdata<'a> {
     pub result_size: usize,
 }
 
-const RESULT_REF_FLAGS: u8 = FfiRefFlag::Leaked.value() | FfiRefFlag::Writable.value();
+const RESULT_REF_FLAGS: u8 = RefDataFlag::Leaked.value() | RefDataFlag::Writable.value();
 
 unsafe extern "C" fn callback(
     cif: *mut ffi_cif,
@@ -51,10 +52,10 @@ unsafe extern "C" fn callback(
     args.push(LuaValue::UserData(
         (*userdata)
             .lua
-            .create_userdata(FfiRef::new(
+            .create_userdata(RefData::new(
                 result_pointer.cast::<()>(),
                 RESULT_REF_FLAGS,
-                FfiRefBounds::new(0, (*userdata).result_size),
+                RefDataBounds::new(0, (*userdata).result_size),
             ))
             .unwrap(),
     ));
@@ -64,10 +65,10 @@ unsafe extern "C" fn callback(
         args.push(LuaValue::UserData(
             (*userdata)
                 .lua
-                .create_userdata(FfiRef::new(
+                .create_userdata(RefData::new(
                     (*arg_pointers.add(i)).cast::<()>(),
                     (*userdata).arg_ref_flags.get(i).unwrap().to_owned(),
-                    FfiRefBounds::new(0, (*userdata).arg_ref_size.get(i).unwrap().to_owned()),
+                    RefDataBounds::new(0, (*userdata).arg_ref_size.get(i).unwrap().to_owned()),
                 ))
                 .unwrap(),
         ));
@@ -76,11 +77,11 @@ unsafe extern "C" fn callback(
     (*userdata).func.call::<_, ()>(args).unwrap();
 }
 
-impl<'a> FfiClosure<'a> {
+impl<'a> ClosureData<'a> {
     pub unsafe fn new(
         cif: *mut ffi_cif,
         userdata: CallbackUserdata<'a>,
-    ) -> LuaResult<FfiClosure<'a>> {
+    ) -> LuaResult<ClosureData<'a>> {
         let (closure, code) = closure_alloc();
         let prep_result = ffi_prep_closure_loc(
             closure,
@@ -96,7 +97,7 @@ impl<'a> FfiClosure<'a> {
                 FFI_STATUS_NAMES[0], FFI_STATUS_NAMES[prep_result as usize]
             )))
         } else {
-            Ok(FfiClosure {
+            Ok(ClosureData {
                 closure,
                 code,
                 userdata,
diff --git a/crates/lune-std-ffi/src/ffi/ffi_lib.rs b/crates/lune-std-ffi/src/data/lib_data.rs
similarity index 60%
rename from crates/lune-std-ffi/src/ffi/ffi_lib.rs
rename to crates/lune-std-ffi/src/data/lib_data.rs
index b071257..211dbda 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_lib.rs
+++ b/crates/lune-std-ffi/src/data/lib_data.rs
@@ -2,19 +2,19 @@ use dlopen2::raw::Library;
 use mlua::prelude::*;
 
 use super::{
+    association,
     association_names::SYM_INNER,
-    ffi_association::set_association,
-    ffi_ref::{FfiRef, FfiRefFlag, UNSIZED_BOUNDS},
+    ref_data::{RefData, RefDataFlag, UNSIZED_BOUNDS},
 };
 
-const LIB_REF_FLAGS: u8 = FfiRefFlag::Offsetable.value()
-    | FfiRefFlag::Readable.value()
-    | FfiRefFlag::Dereferenceable.value()
-    | FfiRefFlag::Function.value();
+const LIB_REF_FLAGS: u8 = RefDataFlag::Offsetable.value()
+    | RefDataFlag::Readable.value()
+    | RefDataFlag::Dereferenceable.value()
+    | RefDataFlag::Function.value();
 
-pub struct FfiLib(Library);
+pub struct LibData(Library);
 
-impl FfiLib {
+impl LibData {
     pub fn new(libname: String) -> LuaResult<Self> {
         match Library::open(libname) {
             Ok(t) => Ok(Self(t)),
@@ -27,7 +27,7 @@ impl FfiLib {
         this: LuaAnyUserData<'lua>,
         name: String,
     ) -> LuaResult<LuaAnyUserData<'lua>> {
-        let lib = this.borrow::<FfiLib>()?;
+        let lib = this.borrow::<LibData>()?;
         let sym = unsafe {
             lib.0
                 .symbol::<*const ()>(name.as_str())
@@ -35,18 +35,18 @@ impl FfiLib {
         };
 
         let ffi_ref =
-            lua.create_userdata(FfiRef::new(sym.cast_mut(), LIB_REF_FLAGS, UNSIZED_BOUNDS))?;
+            lua.create_userdata(RefData::new(sym.cast_mut(), LIB_REF_FLAGS, UNSIZED_BOUNDS))?;
 
-        set_association(lua, SYM_INNER, &ffi_ref, &this)?;
+        association::set(lua, SYM_INNER, &ffi_ref, &this)?;
 
         Ok(ffi_ref)
     }
 }
 
-impl LuaUserData for FfiLib {
+impl LuaUserData for LibData {
     fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
         methods.add_function("find", |lua, (this, name): (LuaAnyUserData, String)| {
-            FfiLib::get_sym(lua, this, name)
+            LibData::get_sym(lua, this, name)
         });
     }
 }
diff --git a/crates/lune-std-ffi/src/data/mod.rs b/crates/lune-std-ffi/src/data/mod.rs
new file mode 100644
index 0000000..6b5de23
--- /dev/null
+++ b/crates/lune-std-ffi/src/data/mod.rs
@@ -0,0 +1,53 @@
+use std::cell::Ref;
+
+use lune_utils::fmt::{pretty_format_value, ValueFormatConfig};
+use mlua::prelude::*;
+
+mod box_data;
+mod callable_data;
+mod closure_data;
+mod lib_data;
+mod ref_data;
+
+pub use crate::{
+    data::{
+        box_data::BoxData,
+        callable_data::CallableData,
+        closure_data::ClosureData,
+        lib_data::LibData,
+        ref_data::{create_nullptr, RefData, RefDataBounds, RefDataFlag},
+    },
+    ffi::{
+        association, num_cast, FfiArgInfo, FfiConvert, FfiData, FfiResultInfo, FfiSignedness,
+        FfiSize,
+    },
+};
+
+// Named registry table names
+mod association_names {
+    pub const REF_INNER: &str = "__ref_inner";
+    pub const SYM_INNER: &str = "__syn_inner";
+}
+
+pub trait GetFfiData {
+    fn get_data_handle(&self) -> LuaResult<Ref<dyn FfiData>>;
+}
+
+impl GetFfiData for LuaAnyUserData<'_> {
+    fn get_data_handle(&self) -> LuaResult<Ref<dyn FfiData>> {
+        if self.is::<BoxData>() {
+            Ok(self.borrow::<BoxData>()? as Ref<dyn FfiData>)
+        } else if self.is::<RefData>() {
+            Ok(self.borrow::<RefData>()? as Ref<dyn FfiData>)
+        // } else if self.is::<FfiRaw>() {
+        // Ok(self.borrow::<FfiRaw>()? as Ref<dyn ReadWriteHandle>)
+        } else {
+            let config = ValueFormatConfig::new();
+            Err(LuaError::external(format!(
+                "Expected FfiBox, FfiRef or FfiRaw. got {}",
+                // what?
+                pretty_format_value(&LuaValue::UserData(self.to_owned()), &config)
+            )))
+        }
+    }
+}
diff --git a/crates/lune-std-ffi/src/ffi/ffi_ref/bounds.rs b/crates/lune-std-ffi/src/data/ref_data/bounds.rs
similarity index 94%
rename from crates/lune-std-ffi/src/ffi/ffi_ref/bounds.rs
rename to crates/lune-std-ffi/src/data/ref_data/bounds.rs
index 9fd8566..cfa1699 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_ref/bounds.rs
+++ b/crates/lune-std-ffi/src/data/ref_data/bounds.rs
@@ -1,17 +1,17 @@
 // Memory range for ref or box data. For boundary checking
-pub struct FfiRefBounds {
+pub struct RefDataBounds {
     // Indicates how much data is above the pointer
     pub(crate) above: usize,
     // Indicates how much data is below the pointer
     pub(crate) below: usize,
 }
 
-pub const UNSIZED_BOUNDS: FfiRefBounds = FfiRefBounds {
+pub const UNSIZED_BOUNDS: RefDataBounds = RefDataBounds {
     above: usize::MAX,
     below: usize::MAX,
 };
 
-impl FfiRefBounds {
+impl RefDataBounds {
     pub fn new(above: usize, below: usize) -> Self {
         Self { above, below }
     }
@@ -88,7 +88,7 @@ impl FfiRefBounds {
     }
 }
 
-impl Clone for FfiRefBounds {
+impl Clone for RefDataBounds {
     fn clone(&self) -> Self {
         Self {
             above: self.above,
diff --git a/crates/lune-std-ffi/src/ffi/ffi_ref/flag.rs b/crates/lune-std-ffi/src/data/ref_data/flag.rs
similarity index 86%
rename from crates/lune-std-ffi/src/ffi/ffi_ref/flag.rs
rename to crates/lune-std-ffi/src/data/ref_data/flag.rs
index 5dd4ec1..3cf3b11 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_ref/flag.rs
+++ b/crates/lune-std-ffi/src/data/ref_data/flag.rs
@@ -1,6 +1,6 @@
-use super::super::bit_mask::*;
+use crate::ffi::bit_mask::*;
 
-pub enum FfiRefFlag {
+pub enum RefDataFlag {
     Leaked,
     Dereferenceable,
     Readable,
@@ -9,7 +9,7 @@ pub enum FfiRefFlag {
     Function,
     Uninit,
 }
-impl FfiRefFlag {
+impl RefDataFlag {
     pub const fn value(&self) -> u8 {
         match self {
             Self::Leaked => U8_MASK1,
diff --git a/crates/lune-std-ffi/src/ffi/ffi_ref/mod.rs b/crates/lune-std-ffi/src/data/ref_data/mod.rs
similarity index 74%
rename from crates/lune-std-ffi/src/ffi/ffi_ref/mod.rs
rename to crates/lune-std-ffi/src/data/ref_data/mod.rs
index 3534e98..4659cef 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_ref/mod.rs
+++ b/crates/lune-std-ffi/src/data/ref_data/mod.rs
@@ -2,24 +2,22 @@ use std::{mem::ManuallyDrop, ptr};
 
 use mlua::prelude::*;
 
-use super::{
-    association_names::REF_INNER,
-    bit_mask::{u8_test, u8_test_not},
-    ffi_association::{get_association, set_association},
-    NativeData,
+use crate::{
+    data::association_names::REF_INNER,
+    ffi::{association, bit_mask::*, FfiData},
 };
 
 mod bounds;
 mod flag;
 
 pub use self::{
-    bounds::{FfiRefBounds, UNSIZED_BOUNDS},
-    flag::FfiRefFlag,
+    bounds::{RefDataBounds, UNSIZED_BOUNDS},
+    flag::RefDataFlag,
 };
 
 // Box:ref():ref() should not be able to modify, Only for external
 const BOX_REF_REF_FLAGS: u8 = 0;
-const UNINIT_REF_FLAGS: u8 = FfiRefFlag::Uninit.value();
+const UNINIT_REF_FLAGS: u8 = RefDataFlag::Uninit.value();
 // | FfiRefFlag::Writable.value()
 // | FfiRefFlag::Readable.value()
 // | FfiRefFlag::Dereferenceable.value()
@@ -32,14 +30,14 @@ const UNINIT_REF_FLAGS: u8 = FfiRefFlag::Uninit.value();
 // If it references an area managed by Lua,
 // the box will remain as long as this reference is alive.
 
-pub struct FfiRef {
+pub struct RefData {
     ptr: ManuallyDrop<Box<*mut ()>>,
     pub flags: u8,
-    pub boundary: FfiRefBounds,
+    pub boundary: RefDataBounds,
 }
 
-impl FfiRef {
-    pub fn new(ptr: *mut (), flags: u8, boundary: FfiRefBounds) -> Self {
+impl RefData {
+    pub fn new(ptr: *mut (), flags: u8, boundary: RefDataBounds) -> Self {
         Self {
             ptr: ManuallyDrop::new(Box::new(ptr)),
             flags,
@@ -60,25 +58,25 @@ impl FfiRef {
         lua: &'lua Lua,
         this: LuaAnyUserData<'lua>,
     ) -> LuaResult<LuaAnyUserData<'lua>> {
-        let target = this.borrow::<FfiRef>()?;
+        let target = this.borrow::<RefData>()?;
 
-        let luaref = lua.create_userdata(FfiRef::new(
+        let luaref = lua.create_userdata(RefData::new(
             ptr::from_ref(&target.ptr) as *mut (),
             BOX_REF_REF_FLAGS,
-            FfiRefBounds {
+            RefDataBounds {
                 below: 0,
                 above: size_of::<usize>(),
             },
         ))?;
 
         // If the ref holds a box, make sure the new ref also holds the box by holding ref
-        set_association(lua, REF_INNER, &luaref, &this)?;
+        association::set(lua, REF_INNER, &luaref, &this)?;
 
         Ok(luaref)
     }
 
     pub unsafe fn deref(&self) -> LuaResult<Self> {
-        u8_test(self.flags, FfiRefFlag::Dereferenceable.value())
+        u8_test(self.flags, RefDataFlag::Dereferenceable.value())
             .then_some(())
             .ok_or_else(|| LuaError::external("This pointer is not dereferenceable."))?;
 
@@ -106,7 +104,7 @@ impl FfiRef {
     }
 
     pub unsafe fn offset(&self, offset: isize) -> LuaResult<Self> {
-        u8_test(self.flags, FfiRefFlag::Offsetable.value())
+        u8_test(self.flags, RefDataFlag::Offsetable.value())
             .then_some(())
             .ok_or_else(|| LuaError::external("This pointer is not offsetable."))?;
 
@@ -132,15 +130,15 @@ impl FfiRef {
     }
 }
 
-impl Drop for FfiRef {
+impl Drop for RefData {
     fn drop(&mut self) {
-        if u8_test_not(self.flags, FfiRefFlag::Leaked.value()) {
+        if u8_test_not(self.flags, RefDataFlag::Leaked.value()) {
             unsafe { ManuallyDrop::drop(&mut self.ptr) };
         }
     }
 }
 
-impl NativeData for FfiRef {
+impl FfiData for RefData {
     fn check_boundary(&self, offset: isize, size: usize) -> bool {
         self.boundary.check_sized(offset, size)
     }
@@ -148,42 +146,42 @@ impl NativeData for FfiRef {
         **self.ptr
     }
     fn is_readable(&self) -> bool {
-        u8_test(self.flags, FfiRefFlag::Readable.value())
+        u8_test(self.flags, RefDataFlag::Readable.value())
     }
     fn is_writable(&self) -> bool {
-        u8_test(self.flags, FfiRefFlag::Writable.value())
+        u8_test(self.flags, RefDataFlag::Writable.value())
     }
 }
 
-impl LuaUserData for FfiRef {
+impl LuaUserData for RefData {
     fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
         // FIXME:
         methods.add_function("deref", |lua, this: LuaAnyUserData| {
-            let inner = get_association(lua, REF_INNER, &this)?;
-            let ffiref = this.borrow::<FfiRef>()?;
+            let inner = association::get(lua, REF_INNER, &this)?;
+            let ffiref = this.borrow::<RefData>()?;
             let result = lua.create_userdata(unsafe { ffiref.deref()? })?;
 
             if let Some(t) = inner {
-                // if let Some(u) = get_association(lua, regname, value) {}
-                set_association(lua, REF_INNER, &result, &t)?;
+                // if let Some(u) = association::get(lua, regname, value) {}
+                association::set(lua, REF_INNER, &result, &t)?;
             }
 
             Ok(result)
         });
         methods.add_function("offset", |lua, (this, offset): (LuaAnyUserData, isize)| {
-            let ffiref = unsafe { this.borrow::<FfiRef>()?.offset(offset)? };
+            let ffiref = unsafe { this.borrow::<RefData>()?.offset(offset)? };
             let userdata = lua.create_userdata(ffiref)?;
 
             // If the ref holds a box, make sure the new ref also holds the box
-            if let Some(t) = get_association(lua, REF_INNER, &this)? {
-                set_association(lua, REF_INNER, &userdata, t)?;
+            if let Some(t) = association::get(lua, REF_INNER, &this)? {
+                association::set(lua, REF_INNER, &userdata, t)?;
             }
 
             Ok(userdata)
         });
         // FIXME:
         methods.add_function("ref", |lua, this: LuaAnyUserData| {
-            let ffiref = FfiRef::luaref(lua, this)?;
+            let ffiref = RefData::luaref(lua, this)?;
             Ok(ffiref)
         });
         methods.add_method("isNull", |_, this, ()| Ok(this.is_nullptr()));
@@ -192,7 +190,7 @@ impl LuaUserData for FfiRef {
 
 pub fn create_nullptr(lua: &Lua) -> LuaResult<LuaAnyUserData> {
     // https://en.cppreference.com/w/cpp/types/nullptr_t
-    lua.create_userdata(FfiRef::new(
+    lua.create_userdata(RefData::new(
         ptr::null_mut::<()>().cast(),
         0,
         // usize::MAX means that nullptr is can be 'any' pointer type
diff --git a/crates/lune-std-ffi/src/ffi/ffi_native/arg.rs b/crates/lune-std-ffi/src/ffi/arg.rs
similarity index 55%
rename from crates/lune-std-ffi/src/ffi/ffi_native/arg.rs
rename to crates/lune-std-ffi/src/ffi/arg.rs
index 9eb06a0..9d895fe 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_native/arg.rs
+++ b/crates/lune-std-ffi/src/ffi/arg.rs
@@ -1,16 +1,16 @@
-use super::NativeConvert;
+use super::FfiConvert;
 
 pub struct FfiArgRefOption {
     pub flag: u8,
 }
 
-pub enum NativeArgType {
+pub enum FfiArgType {
     FfiBox,
     FfiRef(FfiArgRefOption),
 }
 
-pub struct NativeArgInfo {
-    pub conv: *const dyn NativeConvert,
+pub struct FfiArgInfo {
+    pub conv: *const dyn FfiConvert,
     pub size: usize,
     // pub kind: NativeArgType,
 }
diff --git a/crates/lune-std-ffi/src/ffi/ffi_association.rs b/crates/lune-std-ffi/src/ffi/association.rs
similarity index 91%
rename from crates/lune-std-ffi/src/ffi/ffi_association.rs
rename to crates/lune-std-ffi/src/ffi/association.rs
index be15a65..b5c6265 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_association.rs
+++ b/crates/lune-std-ffi/src/ffi/association.rs
@@ -29,12 +29,7 @@ use mlua::prelude::*;
 // You can delete the relationship by changing 'associated' to nil
 
 #[inline]
-pub fn set_association<'lua, T, U>(
-    lua: &'lua Lua,
-    regname: &str,
-    value: T,
-    associated: U,
-) -> LuaResult<()>
+pub fn set<'lua, T, U>(lua: &'lua Lua, regname: &str, value: T, associated: U) -> LuaResult<()>
 where
     T: IntoLua<'lua>,
     U: IntoLua<'lua>,
@@ -61,11 +56,7 @@ where
 // If there is no table in registry, it returns None.
 // If there is no value in table, it returns LuaNil.
 #[inline]
-pub fn get_association<'lua, T>(
-    lua: &'lua Lua,
-    regname: &str,
-    value: T,
-) -> LuaResult<Option<LuaValue<'lua>>>
+pub fn get<'lua, T>(lua: &'lua Lua, regname: &str, value: T) -> LuaResult<Option<LuaValue<'lua>>>
 where
     T: IntoLua<'lua>,
 {
diff --git a/crates/lune-std-ffi/src/ffi/bit_mask.rs b/crates/lune-std-ffi/src/ffi/bit_mask.rs
new file mode 100644
index 0000000..db88474
--- /dev/null
+++ b/crates/lune-std-ffi/src/ffi/bit_mask.rs
@@ -0,0 +1,29 @@
+#![allow(unused)]
+
+pub const U8_MASK1: u8 = 1;
+pub const U8_MASK2: u8 = 2;
+pub const U8_MASK3: u8 = 4;
+pub const U8_MASK4: u8 = 8;
+pub const U8_MASK5: u8 = 16;
+pub const U8_MASK6: u8 = 32;
+pub const U8_MASK7: u8 = 64;
+pub const U8_MASK8: u8 = 128;
+
+#[inline]
+pub fn u8_test(bits: u8, mask: u8) -> bool {
+    bits & mask != 0
+}
+
+#[inline]
+pub fn u8_test_not(bits: u8, mask: u8) -> bool {
+    bits & mask == 0
+}
+
+#[inline]
+pub fn u8_set(bits: u8, mask: u8, val: bool) -> u8 {
+    if val {
+        bits | mask
+    } else {
+        bits & !mask
+    }
+}
diff --git a/crates/lune-std-ffi/src/ffi/cast.rs b/crates/lune-std-ffi/src/ffi/cast.rs
new file mode 100644
index 0000000..76fd18e
--- /dev/null
+++ b/crates/lune-std-ffi/src/ffi/cast.rs
@@ -0,0 +1,22 @@
+use std::cell::Ref;
+
+use mlua::prelude::*;
+use num::cast::AsPrimitive;
+
+use super::FfiData;
+
+#[inline]
+pub fn num_cast<From, Into>(from: &Ref<dyn FfiData>, into: &Ref<dyn FfiData>) -> LuaResult<()>
+where
+    From: AsPrimitive<Into>,
+    Into: 'static + Copy,
+{
+    let from_ptr = unsafe { from.get_pointer().cast::<From>() };
+    let into_ptr = unsafe { into.get_pointer().cast::<Into>() };
+
+    unsafe {
+        *into_ptr = (*from_ptr).as_();
+    }
+
+    Ok(())
+}
diff --git a/crates/lune-std-ffi/src/ffi/ffi_native/cast.rs b/crates/lune-std-ffi/src/ffi/ffi_native/cast.rs
deleted file mode 100644
index b0915f8..0000000
--- a/crates/lune-std-ffi/src/ffi/ffi_native/cast.rs
+++ /dev/null
@@ -1,29 +0,0 @@
-#![allow(clippy::inline_always)]
-
-use std::cell::Ref;
-
-use mlua::prelude::*;
-use num::cast::AsPrimitive;
-
-use super::NativeData;
-
-// Cast T as U
-
-#[inline(always)]
-pub fn native_num_cast<T, U>(
-    from: &Ref<dyn NativeData>,
-    into: &Ref<dyn NativeData>,
-) -> LuaResult<()>
-where
-    T: AsPrimitive<U>,
-    U: 'static + Copy,
-{
-    let from_ptr = unsafe { from.get_pointer().cast::<T>() };
-    let into_ptr = unsafe { into.get_pointer().cast::<U>() };
-
-    unsafe {
-        *into_ptr = (*from_ptr).as_();
-    }
-
-    Ok(())
-}
diff --git a/crates/lune-std-ffi/src/ffi/ffi_native/convert.rs b/crates/lune-std-ffi/src/ffi/ffi_native/convert.rs
deleted file mode 100644
index 4d493e1..0000000
--- a/crates/lune-std-ffi/src/ffi/ffi_native/convert.rs
+++ /dev/null
@@ -1,27 +0,0 @@
-#![allow(clippy::inline_always)]
-
-use std::cell::Ref;
-
-use mlua::prelude::*;
-
-use super::NativeData;
-
-// Handle native data, provide type conversion between luavalue and native types
-pub trait NativeConvert {
-    // Convert luavalue into data, then write into ptr
-    unsafe fn luavalue_into<'lua>(
-        &self,
-        lua: &'lua Lua,
-        offset: isize,
-        data_handle: &Ref<dyn NativeData>,
-        value: LuaValue<'lua>,
-    ) -> LuaResult<()>;
-
-    // Read data from ptr, then convert into luavalue
-    unsafe fn luavalue_from<'lua>(
-        &self,
-        lua: &'lua Lua,
-        offset: isize,
-        data_handle: &Ref<dyn NativeData>,
-    ) -> LuaResult<LuaValue<'lua>>;
-}
diff --git a/crates/lune-std-ffi/src/ffi/ffi_native/data.rs b/crates/lune-std-ffi/src/ffi/ffi_native/data.rs
deleted file mode 100644
index eaa32c6..0000000
--- a/crates/lune-std-ffi/src/ffi/ffi_native/data.rs
+++ /dev/null
@@ -1,40 +0,0 @@
-use std::cell::Ref;
-
-use lune_utils::fmt::{pretty_format_value, ValueFormatConfig};
-use mlua::prelude::*;
-
-use super::super::{FfiBox, FfiRef};
-
-pub trait NativeData {
-    fn check_boundary(&self, offset: isize, size: usize) -> bool;
-    unsafe fn get_pointer(&self) -> *mut ();
-    fn is_writable(&self) -> bool;
-    fn is_readable(&self) -> bool;
-}
-
-pub trait GetNativeData {
-    fn get_data_handle(&self) -> LuaResult<Ref<dyn NativeData>>;
-}
-
-// I tried to remove dyn (which have little bit costs)
-// But, maybe this is best option for now.
-// If remove dyn, we must spam self.is::<>() / self.borrow::<>()?
-// more costly....
-impl GetNativeData for LuaAnyUserData<'_> {
-    fn get_data_handle(&self) -> LuaResult<Ref<dyn NativeData>> {
-        if self.is::<FfiBox>() {
-            Ok(self.borrow::<FfiBox>()? as Ref<dyn NativeData>)
-        } else if self.is::<FfiRef>() {
-            Ok(self.borrow::<FfiRef>()? as Ref<dyn NativeData>)
-        // } else if self.is::<FfiRaw>() {
-        // Ok(self.borrow::<FfiRaw>()? as Ref<dyn ReadWriteHandle>)
-        } else {
-            let config = ValueFormatConfig::new();
-            Err(LuaError::external(format!(
-                "Expected FfiBox, FfiRef or FfiRaw. got {}",
-                // what?
-                pretty_format_value(&LuaValue::UserData(self.to_owned()), &config)
-            )))
-        }
-    }
-}
diff --git a/crates/lune-std-ffi/src/ffi/ffi_native/mod.rs b/crates/lune-std-ffi/src/ffi/ffi_native/mod.rs
deleted file mode 100644
index 4ac89ba..0000000
--- a/crates/lune-std-ffi/src/ffi/ffi_native/mod.rs
+++ /dev/null
@@ -1,25 +0,0 @@
-mod arg;
-mod cast;
-mod convert;
-mod data;
-mod result;
-
-pub trait NativeSize {
-    fn get_size(&self) -> usize;
-}
-
-pub trait NativeSignedness {
-    fn get_signedness(&self) -> bool {
-        false
-    }
-}
-
-pub use self::{
-    arg::NativeArgInfo,
-    cast::native_num_cast,
-    convert::NativeConvert,
-    data::GetNativeData,
-    data::NativeData,
-    result::NativeResultInfo,
-    // result::NativeResultType,
-};
diff --git a/crates/lune-std-ffi/src/libffi_helper.rs b/crates/lune-std-ffi/src/ffi/libffi_helper.rs
similarity index 81%
rename from crates/lune-std-ffi/src/libffi_helper.rs
rename to crates/lune-std-ffi/src/ffi/libffi_helper.rs
index 41b9f6e..2c0d1e0 100644
--- a/crates/lune-std-ffi/src/libffi_helper.rs
+++ b/crates/lune-std-ffi/src/ffi/libffi_helper.rs
@@ -3,8 +3,6 @@ use std::ptr::{self, null_mut};
 use libffi::{low, raw};
 use mlua::prelude::*;
 
-use crate::ffi::FFI_STATUS_NAMES;
-
 // Get ensured size of c-type (raw::libffi_type)
 // See: http://www.chiark.greenend.org.uk/doc/libffi-dev/html/Size-and-Alignment.html
 pub fn get_ensured_size(ffi_type: *mut raw::ffi_type) -> LuaResult<usize> {
@@ -29,3 +27,11 @@ pub fn get_ensured_size(ffi_type: *mut raw::ffi_type) -> LuaResult<usize> {
 }
 
 pub const SIEE_OF_POINTER: usize = size_of::<*mut ()>();
+
+// Converts ffi status into &str
+pub const FFI_STATUS_NAMES: [&str; 4] = [
+    "ffi_status_FFI_OK",
+    "ffi_status_FFI_BAD_TYPEDEF",
+    "ffi_status_FFI_BAD_ABI",
+    "ffi_status_FFI_BAD_ARGTYPE",
+];
diff --git a/crates/lune-std-ffi/src/ffi/mod.rs b/crates/lune-std-ffi/src/ffi/mod.rs
index ef4ae64..c1a6822 100644
--- a/crates/lune-std-ffi/src/ffi/mod.rs
+++ b/crates/lune-std-ffi/src/ffi/mod.rs
@@ -1,71 +1,49 @@
-pub mod ffi_association;
-mod ffi_box;
-mod ffi_callable;
-mod ffi_closure;
-mod ffi_lib;
-mod ffi_native;
-mod ffi_ref;
+use std::cell::Ref;
 
 use mlua::prelude::*;
 
-pub use self::{
-    ffi_box::FfiBox,
-    ffi_callable::FfiCallable,
-    ffi_closure::FfiClosure,
-    ffi_lib::FfiLib,
-    ffi_native::{
-        native_num_cast, GetNativeData, NativeArgInfo, NativeConvert, NativeData, NativeResultInfo,
-        NativeSignedness, NativeSize,
-    },
-    ffi_ref::{create_nullptr, FfiRef, FfiRefFlag},
-};
+mod arg;
+pub mod association;
+pub mod bit_mask;
+mod cast;
+pub mod libffi_helper;
+mod result;
 
-// Named registry table names
-mod association_names {
-    pub const REF_INNER: &str = "__ref_inner";
-    pub const SYM_INNER: &str = "__syn_inner";
+pub trait FfiSize {
+    fn get_size(&self) -> usize;
 }
 
-// Converts ffi status into &str
-pub const FFI_STATUS_NAMES: [&str; 4] = [
-    "ffi_status_FFI_OK",
-    "ffi_status_FFI_BAD_TYPEDEF",
-    "ffi_status_FFI_BAD_ABI",
-    "ffi_status_FFI_BAD_ARGTYPE",
-];
-
-#[allow(unused)]
-pub mod bit_mask {
-    pub const U8_MASK1: u8 = 1;
-    pub const U8_MASK2: u8 = 2;
-    pub const U8_MASK3: u8 = 4;
-    pub const U8_MASK4: u8 = 8;
-    pub const U8_MASK5: u8 = 16;
-    pub const U8_MASK6: u8 = 32;
-    pub const U8_MASK7: u8 = 64;
-    pub const U8_MASK8: u8 = 128;
-
-    #[inline]
-    pub fn u8_test(bits: u8, mask: u8) -> bool {
-        bits & mask != 0
-    }
-
-    #[inline]
-    pub fn u8_test_not(bits: u8, mask: u8) -> bool {
-        bits & mask == 0
-    }
-
-    #[inline]
-    pub fn u8_set(bits: u8, mask: u8, val: bool) -> u8 {
-        if val {
-            bits | mask
-        } else {
-            bits & !mask
-        }
+pub trait FfiSignedness {
+    fn get_signedness(&self) -> bool {
+        false
     }
 }
 
-#[inline]
-pub fn is_integer(num: LuaValue) -> bool {
-    num.is_integer()
+// Provide type conversion between luavalue and ffidata types
+pub trait FfiConvert {
+    // Write LuaValue into FfiData
+    unsafe fn value_into_data<'lua>(
+        &self,
+        lua: &'lua Lua,
+        offset: isize,
+        data_handle: &Ref<dyn FfiData>,
+        value: LuaValue<'lua>,
+    ) -> LuaResult<()>;
+
+    // Read LuaValue from FfiData
+    unsafe fn value_from_data<'lua>(
+        &self,
+        lua: &'lua Lua,
+        offset: isize,
+        data_handle: &Ref<dyn FfiData>,
+    ) -> LuaResult<LuaValue<'lua>>;
 }
+
+pub trait FfiData {
+    fn check_boundary(&self, offset: isize, size: usize) -> bool;
+    unsafe fn get_pointer(&self) -> *mut ();
+    fn is_writable(&self) -> bool;
+    fn is_readable(&self) -> bool;
+}
+
+pub use self::{arg::FfiArgInfo, cast::num_cast, result::FfiResultInfo};
diff --git a/crates/lune-std-ffi/src/ffi/ffi_native/result.rs b/crates/lune-std-ffi/src/ffi/result.rs
similarity index 55%
rename from crates/lune-std-ffi/src/ffi/ffi_native/result.rs
rename to crates/lune-std-ffi/src/ffi/result.rs
index 588aae7..06bd808 100644
--- a/crates/lune-std-ffi/src/ffi/ffi_native/result.rs
+++ b/crates/lune-std-ffi/src/ffi/result.rs
@@ -1,12 +1,12 @@
-use super::NativeConvert;
+use super::FfiConvert;
 
 // pub enum NativeResultType {
 //     FfiBox,
 //     FfiRef,
 // }
 
-pub struct NativeResultInfo {
-    pub conv: *const dyn NativeConvert,
+pub struct FfiResultInfo {
+    pub conv: *const dyn FfiConvert,
     pub size: usize,
     // kind: NativeResultType,
 }
diff --git a/crates/lune-std-ffi/src/lib.rs b/crates/lune-std-ffi/src/lib.rs
index c2fb844..18b9648 100644
--- a/crates/lune-std-ffi/src/lib.rs
+++ b/crates/lune-std-ffi/src/lib.rs
@@ -1,16 +1,16 @@
 #![allow(clippy::cargo_common_metadata)]
 
-use ffi::FfiRef;
+use data::RefData;
 use lune_utils::TableBuilder;
 use mlua::prelude::*;
 
 mod c;
+mod data;
 mod ffi;
-mod libffi_helper;
 
 use crate::{
-    c::{export_ctypes, CFunc, CStruct},
-    ffi::{create_nullptr, is_integer, FfiBox, FfiLib},
+    c::{export_ctypes, CFnInfo, CStructInfo},
+    data::{create_nullptr, BoxData, LibData},
 };
 
 /**
@@ -24,22 +24,21 @@ pub fn module(lua: &Lua) -> LuaResult<LuaTable> {
     let result = TableBuilder::new(lua)?
         .with_values(export_ctypes(lua)?)?
         .with_function("nullRef", |lua, ()| create_nullptr(lua))?
-        .with_function("box", |_lua, size: usize| Ok(FfiBox::new(size)))?
-        .with_function("open", |_lua, name: String| FfiLib::new(name))?
+        .with_function("box", |_lua, size: usize| Ok(BoxData::new(size)))?
+        .with_function("open", |_lua, name: String| LibData::new(name))?
         .with_function("structInfo", |lua, types: LuaTable| {
-            CStruct::from_table(lua, types)
+            CStructInfo::from_table(lua, types)
         })?
-        .with_function("uninitRef", |_lua, ()| Ok(FfiRef::new_uninit()))?
-        .with_function("isInteger", |_lua, num: LuaValue| Ok(is_integer(num)))?
-        .with_function(
-            "funcInfo",
-            |lua, (args, ret): (LuaTable, LuaAnyUserData)| CFunc::new_from_table(lua, args, ret),
-        )?;
+        .with_function("uninitRef", |_lua, ()| Ok(RefData::new_uninit()))?
+        .with_function("isInteger", |_lua, num: LuaValue| Ok(num.is_integer()))?
+        .with_function("fnInfo", |lua, (args, ret): (LuaTable, LuaAnyUserData)| {
+            CFnInfo::new_from_table(lua, args, ret)
+        })?;
 
     #[cfg(debug_assertions)]
     let result = result.with_function("debug_associate", |lua, str: String| {
         println!("WARNING: ffi.debug_associate is GC debug function, which only works for debug build. Do not use this function in production level codes.");
-        crate::ffi::ffi_association::get_table(lua, str.as_ref())
+        ffi::association::get_table(lua, str.as_ref())
     })?;
 
     result.build_readonly()
diff --git a/types/ffi.luau b/types/ffi.luau
index ddcc5e9..9db4647 100644
--- a/types/ffi.luau
+++ b/types/ffi.luau
@@ -1,37 +1,57 @@
 -- NOTE: T is a unique identifier for the `CType` and R is the closest Lua type.
-export type CType<T, R> = {
+export type CTypeInfo<T, R> = {
 	size: number,
 	signedness: boolean,
 
-	ptr: (self: CType<T, R>) -> CPtr<R>,
-	box: (self: CType<T, R>, val: R) -> Box,
-	-- FIXME: recursive types; ud should be CTypes
-	from: (self: CType<T, R>, ud: any, offset: number?) -> R,
-	into: (self: CType<T, R>, ud: any, value: R, offset: number?) -> (),
-	arr: (self: CType<T, R>, len: number) -> CArr<R>,
-	-- FIXME: recursive types; intoType should be CTypes
-	cast: <F, I>(self: CType<T, R>, intoType: any, from: F, into: I) -> (),
+	-- subtype
+	ptrInfo: (self: CTypeInfo<T, R>) -> CPtrInfo<CTypeInfo<T, R>>,
+	arrInfo: (self: CTypeInfo<T, R>, len: number) -> CArrInfo<CTypeInfo<T, R>, R>,
+
+	-- realize
+	box: (self: CTypeInfo<T, R>, val: R) -> Box,
+	fromData: (self: CTypeInfo<T, R>, data: (Ref|Box), offset: number?) -> R,
+	intoData: (self: CTypeInfo<T, R>, data: (Ref|Box), value: R, offset: number?) -> (),
+	
+	-- FIXME: recursive types; 'intoType' should be CTypes
+	cast: (self: CTypeInfo<T, R>, intoType: any, fromData: (Ref|Box), intoData: (Ref|Box)) -> (),
 } & { ["__phantom"]: T }
 
-export type CPtr<T> = {
+export type CPtrInfo<T> = {
 	size: number,
-	inner: T?,
+	inner: T,
+
+	-- subtype
+	-- FIXME: recursive types; 'any' should be CPtrInfo
+	arrInfo: (self: CPtrInfo<T>, len: number) -> any,
+	ptrInfo: (self: CPtrInfo<T>) -> any,
 }
 
-export type CArr<T> = {
+export type CArrInfo<T, R> = {
 	size: number,
 	length: number,
-	inner: { T }?,
+	inner: T,
 
-	offset: (self: CArr<T>, offset: number) -> number,
-	ptr: (self: CArr<T>) -> CPtr<{ T }>,
-	box: (self: CArr<T>, table: { T }) -> Box,
-	-- FIXME: recursive types; ud should be CTypes
-	from: (self: CArr<T>, ud: any, offset: number?) -> { T },
-	into: (self: CArr<T>, ud: any, value: { T }, offset: number?) -> (),
+	-- subtype
+	ptrInfo: (self: CArrInfo<T, R>) -> CPtrInfo<T>,
+
+	-- realize
+	box: (self: CArrInfo<T, R>, table: { T }) -> Box,
+	fromData: (self: CArrInfo<T, R>, data: (Ref|Box), offset: number?) -> { T },
+	intoData: (self: CArrInfo<T, R>, data: (Ref|Box), value: { T }, offset: number?) -> (),
+
+	offset: (self: CArrInfo<T, R>, offset: number) -> number,
 }
 
-type NumCType<T> = CType<T, number>
+export type CFuncInfo = {
+	callable: (self: CFuncInfo, functionRef: Ref) -> Callable,
+}
+
+export type CStructInfo = {
+	arrInfo: (self: CStructInfo, len: number) -> CArrInfo<CStructInfo, {any}>,
+	ptrInfo: (self: CStructInfo) -> CPtrInfo<CStructInfo>,
+}
+
+type NumCType<T> = CTypeInfo<T, (number|any)>
 
 -- Fixed size Rust-style types --
 export type u8 = NumCType<"u8">
@@ -64,10 +84,6 @@ export type ulong = NumCType<"ulong">
 export type longlong = NumCType<"longlong">
 export type ulonglong = NumCType<"ulonglong">
 
-export type CFn = {
-	caller: (self: CFn, fnPtr: Ref) -> Callable,
-}
-
 export type CTypes =
 	| u8
 	| u16
@@ -96,12 +112,15 @@ export type CTypes =
 	| ulong
 	| longlong
 	| ulonglong
+	| CArrInfo<CTypes, any>
+	| CPtrInfo<CTypes>
+	| CFuncInfo
 
 export type Ref = {
 	deref: (self: Ref) -> Ref,
 	offset: (self: Ref, offset: number) -> Ref,
 	ref: (self: Ref) -> Ref,
-	isNullptr: (self: Ref) -> boolean,
+	isNull: (self: Ref) -> boolean,
 }
 
 export type Box = {
@@ -112,12 +131,12 @@ export type Box = {
 	ref: (self: Box, offset: number?) -> Ref,
 }
 
-export type Library = {
-	find: (self: Library, sym: string) -> Ref,
+export type Lib = {
+	find: (self: Lib, sym: string) -> Ref,
 }
 
 export type Callable = {
-	call: (self: Callable, retPtr: Ref, ...Box) -> (),
+	call: (self: Callable, result: Ref, ...(Ref | Box))->();
 }
 
 local ffi = {}
@@ -151,17 +170,19 @@ ffi.ulong = {} :: ulong
 ffi.longlong = {} :: longlong
 ffi.ulonglong = {} :: ulonglong
 
-ffi.nullptr = {} :: Ref
+function ffi.nullRef(): Ref
+	return nil :: any
+end
 
 function ffi.box(size: number): Box
 	return nil :: any
 end
 
-function ffi.open(path: string): Library
+function ffi.open(name: string): Lib
 	return nil :: any
 end
 
-function ffi.ref(): Ref
+function ffi.uninitRef(): Ref
 	return nil :: any
 end
 
@@ -169,7 +190,7 @@ function ffi.isInteger<T>(val: T): boolean
 	return nil :: any
 end
 
-function ffi.fn<T>(args: { CTypes }, ret: CTypes): CFn
+function ffi.funcInfo<T>(args: { CTypes }, ret: CTypes): CFuncInfo
 	return nil :: any
 end