diff --git a/.github/workflows/python-checks.yaml b/.github/workflows/python-checks.yaml
new file mode 100644
index 0000000..a968533
--- /dev/null
+++ b/.github/workflows/python-checks.yaml
@@ -0,0 +1,55 @@
+name: CI
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  format:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python 3.12.8
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.12.8'
+    - name: Install Black
+      run: pip install black
+    - name: Apply Black formatting
+      run: black .
+    - name: Commit formatting changes
+      run: |
+        git config --local user.email "action@github.com"
+        git config --local user.name "GitHub Action"
+        git add -A
+        git commit -m "Apply Black formatting" || echo "No changes to commit"
+
+  lint:
+    needs: format
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python 3.12.8
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.12.8'
+    - name: Install Ruff
+      run: pip install ruff
+    - name: Run Ruff linting
+      run: ruff check .
+
+  typecheck:
+    needs: format
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python 3.12.8
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.12.8'
+    - name: Install mypy
+      run: pip install mypy
+    - name: Run type checks
+      run: mypy .
diff --git a/test-ci.py b/test-ci.py
new file mode 100644
index 0000000..6458eb4
--- /dev/null
+++ b/test-ci.py
@@ -0,0 +1,5 @@
+def greet(name: int) -> str:
+    print("Hello, " + name + "!")
+    return 42
+
+greet("world")