diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..a47119c
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,81 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  lint-format:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: "3.10"
+
+      - name: Set up uv
+        uses: astral-sh/setup-uv@v5
+
+      - name: Install dependencies
+        run: uv sync --frozen --all-extras --dev
+
+      - name: Run Ruff lint
+        run: uv run ruff check .
+
+      - name: Check Ruff formatting
+        run: uv run ruff format --check .
+
+  unit-tests:
+    runs-on: ubuntu-latest
+
+    env:
+      OPENAI_API_KEY: test-key
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: "3.10"
+
+      - name: Set up uv
+        uses: astral-sh/setup-uv@v5
+
+      - name: Install dependencies
+        run: uv sync --frozen --all-extras --dev
+
+      - name: Run unit tests
+        run: uv run pytest tests --ignore=tests/e2e
+
+  e2e-tests:
+    runs-on: ubuntu-latest
+
+    env:
+      OPENAI_API_KEY: test-key
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+
+      - name: Set up Python
+        uses: actions/setup-python@v6
+        with:
+          python-version: "3.10"
+
+      - name: Set up uv
+        uses: astral-sh/setup-uv@v5
+
+      - name: Install dependencies
+        run: uv sync --frozen --all-extras --dev
+
+      - name: Run e2e tests
+        run: uv run pytest tests/e2e -o addopts=''
diff --git a/src/specode/__init__.py b/src/specode/__init__.py
index b8c6ad5..4f237bc 100644
--- a/src/specode/__init__.py
+++ b/src/specode/__init__.py
@@ -3,4 +3,3 @@
 __all__ = ["__version__"]
 
 __version__ = "0.1.0"
-
diff --git a/tests/e2e/test_cli_process.py b/tests/e2e/test_cli_process.py
index 816ca92..3f430fe 100644
--- a/tests/e2e/test_cli_process.py
+++ b/tests/e2e/test_cli_process.py
@@ -79,7 +79,9 @@ def test_specode_exits_with_configuration_error_when_openai_api_key_is_missing(
     tmp_path: Path,
 ) -> None:
     result, env = _run_specode(tmp_path, stdin="", extra_env={"OPENAI_API_KEY": ""})
-    diagnostics = _format_diagnostics(env, result.stdout, result.stderr, returncode=result.returncode)
+    diagnostics = _format_diagnostics(
+        env, result.stdout, result.stderr, returncode=result.returncode
+    )
 
     assert result.returncode == 1, diagnostics
     assert "Configuration Error" in result.stdout, diagnostics
@@ -92,7 +94,9 @@ def test_specode_handles_help_then_exit_without_calling_a_model(tmp_path: Path)
         stdin="/help\n/exit\n",
         extra_env={"OPENAI_API_KEY": "test-key"},
     )
-    diagnostics = _format_diagnostics(env, result.stdout, result.stderr, returncode=result.returncode)
+    diagnostics = _format_diagnostics(
+        env, result.stdout, result.stderr, returncode=result.returncode
+    )
 
     assert result.returncode == 0, diagnostics
     assert "Type / for commands" in result.stdout, diagnostics
diff --git a/tests/e2e/test_terminal_pty.py b/tests/e2e/test_terminal_pty.py
index 4a0cb29..4bf43bf 100644
--- a/tests/e2e/test_terminal_pty.py
+++ b/tests/e2e/test_terminal_pty.py
@@ -21,9 +21,7 @@
 REPO_ROOT = Path(__file__).resolve().parents[2]
 COMMAND = "uv run specode"
 PTY_TIMEOUT_SECONDS = 4
-ANSI_ESCAPE_PATTERN = re.compile(
-    r"\x1B(?:[@-Z\\-_]|\[[0-?]*[ -/]*[@-~]|\][^\x07]*(?:\x07|\x1B\\))"
-)
+ANSI_ESCAPE_PATTERN = re.compile(r"\x1B(?:[@-Z\\-_]|\[[0-?]*[ -/]*[@-~]|\][^\x07]*(?:\x07|\x1B\\))")
 
 
 def _isolated_env(tmp_path: Path) -> dict[str, str]:
diff --git a/tests/test_config.py b/tests/test_config.py
index eee327a..bb5fd3a 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -9,7 +9,9 @@
 )
 
 
-def test_raises_a_clear_error_when_openai_api_key_is_missing(monkeypatch: pytest.MonkeyPatch) -> None:
+def test_raises_a_clear_error_when_openai_api_key_is_missing(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
     monkeypatch.setenv("OPENAI_API_KEY", "")
 
     with pytest.raises(ConfigurationError) as exc_info: