diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 4e0f08c..476384e 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -17,6 +17,9 @@ jobs:
         with:
           components: rustfmt, clippy
 
+      - name: Install project tools
+        uses: ok-nick/setup-aftman@v0.3.0
+
       - name: Rustfmt
         run: cargo fmt -- --check
 
@@ -27,10 +30,7 @@ jobs:
         run: cargo clippy
 
       - name: Test - Lune
-        run: cargo test --package lune
-
-      - name: Test - Lune Roblox
-        run: cargo test --package lune-roblox
+        run: just test
 
       - name: Test - CLI
-        run: cargo test --package lune-cli
+        run: just test-cli
diff --git a/.justfile b/.justfile
new file mode 100644
index 0000000..6111fac
--- /dev/null
+++ b/.justfile
@@ -0,0 +1,7 @@
+# Run tests for the Lune library
+test:
+	cargo test --package lune -- --test-threads 1
+
+# Run tests for the Lune CLI
+test-cli:
+	cargo test --package lune-cli
diff --git a/aftman.toml b/aftman.toml
index 4644129..ffc23c0 100644
--- a/aftman.toml
+++ b/aftman.toml
@@ -1,4 +1,5 @@
 [tools]
+just = "readysetplay/just@1.8.0"
 luau-lsp = "JohnnyMorganz/luau-lsp@1.15.0"
 selene = "Kampfkarren/selene@0.24.0"
 stylua = "JohnnyMorganz/StyLua@0.16.0"
diff --git a/packages/lib-roblox/src/instance/mod.rs b/packages/lib-roblox/src/instance/mod.rs
index aa1e993..d62dfbf 100644
--- a/packages/lib-roblox/src/instance/mod.rs
+++ b/packages/lib-roblox/src/instance/mod.rs
@@ -228,7 +228,7 @@ impl Instance {
         // keep track of all current instance reference structs
         let dom = INTERNAL_DOM
             .try_read()
-            .expect("Failed to get write access to document");
+            .expect("Failed to get read access to document");
         dom.get_by_ref(self.dom_ref).is_none()
     }
 
diff --git a/packages/lib/src/tests.rs b/packages/lib/src/tests.rs
index c6f3c64..1a5da82 100644
--- a/packages/lib/src/tests.rs
+++ b/packages/lib/src/tests.rs
@@ -93,27 +93,33 @@ create_tests! {
 
 #[cfg(feature = "roblox")]
 create_tests! {
-    roblox_axes: "roblox/datatypes/Axes",
-    roblox_brick_color: "roblox/datatypes/BrickColor",
-    roblox_cframe: "roblox/datatypes/CFrame",
-    roblox_color3: "roblox/datatypes/Color3",
-    roblox_color_sequence: "roblox/datatypes/ColorSequence",
-    roblox_color_sequence_keypoint: "roblox/datatypes/ColorSequenceKeypoint",
-    roblox_enum: "roblox/datatypes/Enum",
-    roblox_faces: "roblox/datatypes/Faces",
-    roblox_font: "roblox/datatypes/Font",
-    roblox_number_range: "roblox/datatypes/NumberRange",
-    roblox_number_sequence: "roblox/datatypes/NumberSequence",
-    roblox_number_sequence_keypoint: "roblox/datatypes/NumberSequenceKeypoint",
-    roblox_physical_properties: "roblox/datatypes/PhysicalProperties",
-    roblox_ray: "roblox/datatypes/Ray",
-    roblox_rect: "roblox/datatypes/Rect",
-    roblox_udim: "roblox/datatypes/UDim",
-    roblox_udim2: "roblox/datatypes/UDim2",
-    roblox_region3: "roblox/datatypes/Region3",
-    roblox_region3int16: "roblox/datatypes/Region3int16",
-    roblox_vector2: "roblox/datatypes/Vector2",
-    roblox_vector2int16: "roblox/datatypes/Vector2int16",
-    roblox_vector3: "roblox/datatypes/Vector3",
-    roblox_vector3int16: "roblox/datatypes/Vector3int16",
+    roblox_datatype_axes: "roblox/datatypes/Axes",
+    roblox_datatype_brick_color: "roblox/datatypes/BrickColor",
+    roblox_datatype_cframe: "roblox/datatypes/CFrame",
+    roblox_datatype_color3: "roblox/datatypes/Color3",
+    roblox_datatype_color_sequence: "roblox/datatypes/ColorSequence",
+    roblox_datatype_color_sequence_keypoint: "roblox/datatypes/ColorSequenceKeypoint",
+    roblox_datatype_enum: "roblox/datatypes/Enum",
+    roblox_datatype_faces: "roblox/datatypes/Faces",
+    roblox_datatype_font: "roblox/datatypes/Font",
+    roblox_datatype_number_range: "roblox/datatypes/NumberRange",
+    roblox_datatype_number_sequence: "roblox/datatypes/NumberSequence",
+    roblox_datatype_number_sequence_keypoint: "roblox/datatypes/NumberSequenceKeypoint",
+    roblox_datatype_physical_properties: "roblox/datatypes/PhysicalProperties",
+    roblox_datatype_ray: "roblox/datatypes/Ray",
+    roblox_datatype_rect: "roblox/datatypes/Rect",
+    roblox_datatype_udim: "roblox/datatypes/UDim",
+    roblox_datatype_udim2: "roblox/datatypes/UDim2",
+    roblox_datatype_region3: "roblox/datatypes/Region3",
+    roblox_datatype_region3int16: "roblox/datatypes/Region3int16",
+    roblox_datatype_vector2: "roblox/datatypes/Vector2",
+    roblox_datatype_vector2int16: "roblox/datatypes/Vector2int16",
+    roblox_datatype_vector3: "roblox/datatypes/Vector3",
+    roblox_datatype_vector3int16: "roblox/datatypes/Vector3int16",
+    roblox_files_read_model: "roblox/files/readModelFile",
+    roblox_files_read_place: "roblox/files/readPlaceFile",
+    roblox_files_write_model: "roblox/files/writeModelFile",
+    roblox_files_write_place: "roblox/files/writePlaceFile",
+    roblox_instance_new: "roblox/instance/new",
+    roblox_instance_properties: "roblox/instance/properties",
 }