diff --git a/.github/workflows/style.yml b/.github/workflows/style.yml
new file mode 100644
index 0000000..ab9fc31
--- /dev/null
+++ b/.github/workflows/style.yml
@@ -0,0 +1,16 @@
+# The mechanical house-style rules: SPDX header, no Sphinx roles in
+# docstrings, no link to the .github repo from a page, no README badges or
+# status banner. Pull requests check the changed files; a manual run checks
+# every file. Paths that aren't ours go in .style-exclude.
+name: Style
+
+on:
+  pull_request:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  style:
+    uses: PyDevices/.github/.github/workflows/reusable-style-check.yml@publishing-v20
diff --git a/ports/cpython/tests/test_callback_lifetime.py b/ports/cpython/tests/test_callback_lifetime.py
index 996e08f..fb354c3 100644
--- a/ports/cpython/tests/test_callback_lifetime.py
+++ b/ports/cpython/tests/test_callback_lifetime.py
@@ -1,3 +1,5 @@
+# SPDX-FileCopyrightText: 2026 Brad Barnett
+#
 # SPDX-License-Identifier: MIT
 """Lifetime of Python callbacks registered with add_event_cb.
 
diff --git a/ports/cpython/tests/test_callback_references.py b/ports/cpython/tests/test_callback_references.py
index 0669f61..3bc1246 100644
--- a/ports/cpython/tests/test_callback_references.py
+++ b/ports/cpython/tests/test_callback_references.py
@@ -1,3 +1,5 @@
+# SPDX-FileCopyrightText: 2026 Brad Barnett
+#
 # SPDX-License-Identifier: MIT
 """References a callback trampoline holds while LVGL calls into Python.
 
diff --git a/ports/cpython/tests/test_free_threading.py b/ports/cpython/tests/test_free_threading.py
index db4da58..858b91b 100644
--- a/ports/cpython/tests/test_free_threading.py
+++ b/ports/cpython/tests/test_free_threading.py
@@ -1,3 +1,5 @@
+# SPDX-FileCopyrightText: 2026 Brad Barnett
+#
 # SPDX-License-Identifier: MIT
 """lvgl on a free-threaded Python (3.13t and later).
 
diff --git a/ports/cpython/tests/test_jpeg_decoder.py b/ports/cpython/tests/test_jpeg_decoder.py
index b0938ec..e7d1b43 100644
--- a/ports/cpython/tests/test_jpeg_decoder.py
+++ b/ports/cpython/tests/test_jpeg_decoder.py
@@ -1,3 +1,5 @@
+# SPDX-FileCopyrightText: 2026 Brad Barnett
+#
 # SPDX-License-Identifier: MIT
 """JPEG images draw scaled and contained, as they do on MicroPython.
 
diff --git a/ports/cpython/tests/test_lvgl_init.py b/ports/cpython/tests/test_lvgl_init.py
index 28b2372..e2cfd7f 100644
--- a/ports/cpython/tests/test_lvgl_init.py
+++ b/ports/cpython/tests/test_lvgl_init.py
@@ -1,3 +1,5 @@
+# SPDX-FileCopyrightText: 2026 Brad Barnett
+#
 # SPDX-License-Identifier: MIT
 """Unit tests for the native lvgl CPython extension."""
 
diff --git a/ports/cpython/tests/test_runtime_references.py b/ports/cpython/tests/test_runtime_references.py
index 02cf056..e614245 100644
--- a/ports/cpython/tests/test_runtime_references.py
+++ b/ports/cpython/tests/test_runtime_references.py
@@ -1,3 +1,5 @@
+# SPDX-FileCopyrightText: 2026 Brad Barnett
+#
 # SPDX-License-Identifier: MIT
 """Reference counts and buffer exports the runtime hands across to LVGL.
 
diff --git a/ports/cpython/tests/test_struct_callback_lifetime.py b/ports/cpython/tests/test_struct_callback_lifetime.py
index 4641321..0a17929 100644
--- a/ports/cpython/tests/test_struct_callback_lifetime.py
+++ b/ports/cpython/tests/test_struct_callback_lifetime.py
@@ -1,3 +1,5 @@
+# SPDX-FileCopyrightText: 2026 Brad Barnett
+#
 # SPDX-License-Identifier: MIT
 """Lifetime of Python callbacks set on animations and timers.