diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
new file mode 100644
index 0000000..30fca4c
--- /dev/null
+++ b/.github/workflows/tests.yml
@@ -0,0 +1,44 @@
+---
+name: Tests
+
+on:
+  workflow_call:
+  pull_request:
+
+jobs:
+  yamllint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check Out Sources
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Lint yml files
+        uses: ibiqlik/action-yamllint@v3
+        with:
+          strict: true
+  markdownlint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check Out Sources
+        uses: actions/checkout@v2
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@359bebbc29cbe6c87da6bc9ea3bc930432750108
+        with:
+          ruby-version: '3.1'
+      - name: Install mdl
+        run: gem install mdl
+      - name: Lint files
+        run: mdl .
+  swiftlint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check Out Sources
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Lint Files
+        uses: norio-nomura/action-swiftlint@3.2.1
+        with:
+          args: --strict
+...
diff --git a/README.md b/README.md
index d3cfd7e..26c0131 100644
--- a/README.md
+++ b/README.md
@@ -1 +1 @@
-# ZPack
\ No newline at end of file
+# ZPack
diff --git a/Sources/ZPack/Extensions/Metal/MTLPackedFloat3+Extension.swift b/Sources/ZPack/Extensions/Metal/MTLPackedFloat3+Extension.swift
index d1bdc9f..7beb65d 100644
--- a/Sources/ZPack/Extensions/Metal/MTLPackedFloat3+Extension.swift
+++ b/Sources/ZPack/Extensions/Metal/MTLPackedFloat3+Extension.swift
@@ -1,14 +1,14 @@
 import Metal
 import simd
 
-public extension MTLPackedFloat3 {
-    var unpacked: simd_float3 {
+extension MTLPackedFloat3 {
+    public var unpacked: simd_float3 {
         simd_float3(x, y, z)
     }
-    var float4WithZero: simd_float4 {
+    public var float4WithZero: simd_float4 {
         simd_make_float4(x, y, z, 0)
     }
-    var float4WithOne: simd_float4 {
+    public var float4WithOne: simd_float4 {
         simd_make_float4(x, y, z, 1)
     }
 }
diff --git a/Sources/ZPack/Extensions/Swift/Float+Extension.swift b/Sources/ZPack/Extensions/Swift/Float+Extension.swift
index 4901809..f7205b4 100644
--- a/Sources/ZPack/Extensions/Swift/Float+Extension.swift
+++ b/Sources/ZPack/Extensions/Swift/Float+Extension.swift
@@ -1,8 +1,8 @@
-public extension Float {
-    var radians: Float {
+extension Float {
+    public var radians: Float {
         self / 180 * .pi
     }
-    var half: Float16 {
+    public var half: Float16 {
         Float16(self)
     }
 }
diff --git a/Sources/ZPack/Extensions/simd/simd_float3+Extension.swift b/Sources/ZPack/Extensions/simd/simd_float3+Extension.swift
index 18f00a2..5ed6728 100644
--- a/Sources/ZPack/Extensions/simd/simd_float3+Extension.swift
+++ b/Sources/ZPack/Extensions/simd/simd_float3+Extension.swift
@@ -1,14 +1,14 @@
 import Metal
 import simd
 
-public extension simd_float3 {
-    var packed: MTLPackedFloat3 {
+extension simd_float3 {
+    public var packed: MTLPackedFloat3 {
         MTLPackedFloat3Make(x, y, z)
     }
-    var float4WithZero: simd_float4 {
+    public var float4WithZero: simd_float4 {
         simd_make_float4(x, y, z, 0)
     }
-    var float4WithOne: simd_float4 {
+    public var float4WithOne: simd_float4 {
         simd_make_float4(x, y, z, 1)
     }
     public var norm: Float {
diff --git a/Sources/ZPack/Extensions/simd/simd_float3x3+Extension.swift b/Sources/ZPack/Extensions/simd/simd_float3x3+Extension.swift
index 9b6998b..4a31d16 100644
--- a/Sources/ZPack/Extensions/simd/simd_float3x3+Extension.swift
+++ b/Sources/ZPack/Extensions/simd/simd_float3x3+Extension.swift
@@ -1,10 +1,10 @@
 import simd
 
-public extension simd_float3x3 {
-    static var identity: simd_float3x3 {
+extension simd_float3x3 {
+    public static var identity: simd_float3x3 {
         matrix_identity_float3x3
     }
-    static func from(directionVector binormal: simd_float3) -> simd_float3x3 {
+    public static func from(directionVector binormal: simd_float3) -> simd_float3x3 {
         assert(length(binormal) == 1)
         var normal = simd_float3.random()
         normal.normalize()
@@ -16,7 +16,7 @@ public extension simd_float3x3 {
         assert(dot(tangent, binormal) == 0)
         return simd_float3x3(tangent, normal, -binormal)
     }
-    var expanded: simd_float4x4 {
+    public var expanded: simd_float4x4 {
         simd_float4x4(simd_float4(columns.0, 0),
                       simd_float4(columns.1, 0),
                       simd_float4(columns.2, 0),
diff --git a/Sources/ZPack/Extensions/simd/simd_float4+Extension.swift b/Sources/ZPack/Extensions/simd/simd_float4+Extension.swift
index 1f56baa..e48c0f1 100644
--- a/Sources/ZPack/Extensions/simd/simd_float4+Extension.swift
+++ b/Sources/ZPack/Extensions/simd/simd_float4+Extension.swift
@@ -1,13 +1,13 @@
 import simd
 
-public extension simd_float4 {
-    var xyz: simd_float3 {
+extension simd_float4 {
+    public var xyz: simd_float3 {
         simd_make_float3(x, y, z)
     }
-    var zyxw: simd_float4 {
+    public var zyxw: simd_float4 {
         simd_float4(z, y, x, w)
     }
-    var norm: Float {
+    public var norm: Float {
         length(self)
     }
 
diff --git a/Sources/ZPack/Extensions/simd/simd_float4x3+Extension.swift b/Sources/ZPack/Extensions/simd/simd_float4x3+Extension.swift
index 279e9fd..6938705 100644
--- a/Sources/ZPack/Extensions/simd/simd_float4x3+Extension.swift
+++ b/Sources/ZPack/Extensions/simd/simd_float4x3+Extension.swift
@@ -1,8 +1,8 @@
 import Metal
 import simd
 
-public extension simd_float4x3 {
-    var packed: MTLPackedFloat4x3 {
+extension simd_float4x3 {
+    public var packed: MTLPackedFloat4x3 {
         MTLPackedFloat4x3(columns: (columns.0.packed,
                                     columns.1.packed,
                                     columns.2.packed,