diff --git a/.github/workflows/Todo.md b/.github/workflows/TODO.md
similarity index 100%
rename from .github/workflows/Todo.md
rename to .github/workflows/TODO.md
diff --git a/Todo.md b/TODO.md
similarity index 100%
rename from Todo.md
rename to TODO.md
diff --git a/docs/guides/administrator/Readme.md b/docs/guides/administrator/README.md
similarity index 100%
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diff --git a/docs/guides/enterprise/Readme.md b/docs/guides/enterprise/README.md
similarity index 100%
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diff --git a/docs/guides/user/Readme.md b/docs/guides/user/README.md
similarity index 100%
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diff --git a/group_vars/all/Todo.md b/group_vars/all/TODO.md
similarity index 100%
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diff --git a/roles/Todo.md b/roles/TODO.md
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diff --git a/roles/desk-nextcloud/Todo.md b/roles/desk-nextcloud/TODO.md
similarity index 100%
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diff --git a/roles/dev-npm/Todo.md b/roles/dev-npm/TODO.md
similarity index 100%
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diff --git a/roles/docker-compose/Todo.md b/roles/docker-compose/TODO.md
similarity index 100%
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diff --git a/roles/pkgmgr-install/Todo.md b/roles/pkgmgr-install/TODO.md
similarity index 100%
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diff --git a/roles/srv-core/Todo.md b/roles/srv-core/TODO.md
similarity index 100%
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diff --git a/roles/srv-proxy-core/Todo.md b/roles/srv-proxy-core/TODO.md
similarity index 100%
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diff --git a/roles/srv-proxy-core/templates/location/Todo.md b/roles/srv-proxy-core/templates/location/TODO.md
similarity index 100%
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diff --git a/roles/svc-db-postgres/Todo.md b/roles/svc-db-postgres/TODO.md
similarity index 100%
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diff --git a/roles/svc-opt-keyboard-color/Todo.md b/roles/svc-opt-keyboard-color/TODO.md
similarity index 100%
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diff --git a/roles/svc-opt-ssd-hdd/Todo.md b/roles/svc-opt-ssd-hdd/TODO.md
similarity index 100%
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diff --git a/roles/sys-ctl-bkp-docker-2-loc/Todo.md b/roles/sys-ctl-bkp-docker-2-loc/TODO.md
similarity index 100%
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diff --git a/roles/web-app-akaunting/Todo.md b/roles/web-app-akaunting/TODO.md
similarity index 100%
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diff --git a/roles/web-app-bookwyrm/Todo.md b/roles/web-app-bookwyrm/TODO.md
similarity index 100%
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diff --git a/roles/web-app-chess/Readme.md b/roles/web-app-chess/README.md
similarity index 100%
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diff --git a/roles/web-app-discourse/Todo.md b/roles/web-app-discourse/TODO.md
similarity index 100%
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diff --git a/roles/web-app-jenkins/Todo.md b/roles/web-app-jenkins/TODO.md
similarity index 100%
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diff --git a/roles/web-app-keycloak/Todo.md b/roles/web-app-keycloak/TODO.md
similarity index 100%
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diff --git a/roles/web-app-keycloak/tasks/Todo.md b/roles/web-app-keycloak/tasks/TODO.md
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diff --git a/roles/web-app-mailu/Todo.md b/roles/web-app-mailu/TODO.md
similarity index 100%
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diff --git a/roles/web-app-matrix/Todo.md b/roles/web-app-matrix/TODO.md
similarity index 100%
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diff --git a/roles/web-app-nextcloud/Todo.md b/roles/web-app-nextcloud/TODO.md
similarity index 100%
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diff --git a/roles/web-app-oauth2-proxy/Todo.md b/roles/web-app-oauth2-proxy/TODO.md
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diff --git a/roles/web-app-peertube/Todo.md b/roles/web-app-peertube/TODO.md
similarity index 100%
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diff --git a/roles/web-app-phpldapadmin/Todo.md b/roles/web-app-phpldapadmin/TODO.md
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diff --git a/roles/web-app-postmarks/Todo.md b/roles/web-app-postmarks/TODO.md
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diff --git a/roles/web-app-pretix/Readme.md b/roles/web-app-pretix/README.md
similarity index 100%
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rename to roles/web-app-pretix/README.md
diff --git a/roles/web-app-socialhome/Todo.md b/roles/web-app-socialhome/TODO.md
similarity index 100%
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rename to roles/web-app-socialhome/TODO.md
diff --git a/roles/web-opt-rdr-www/Todo.md b/roles/web-opt-rdr-www/TODO.md
similarity index 100%
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diff --git a/roles/web-svc-logout/Todo.md b/roles/web-svc-logout/TODO.md
similarity index 100%
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diff --git a/tests/integration/Todo.md b/tests/integration/TODO.md
similarity index 100%
rename from tests/integration/Todo.md
rename to tests/integration/TODO.md
diff --git a/tests/integration/test_filename_conventions.py b/tests/integration/test_filename_conventions.py
new file mode 100644
index 00000000..95b94fb5
--- /dev/null
+++ b/tests/integration/test_filename_conventions.py
@@ -0,0 +1,27 @@
+import os
+import unittest
+
+class TestFilenameConventions(unittest.TestCase):
+    """
+    Integration test to ensure README.md and TODO.md files
+    are always written in uppercase (README.md / TODO.md).
+    """
+
+    def test_readme_and_todo_filenames_are_uppercase(self):
+        bad_files = []
+        for root, _, files in os.walk("."):
+            for filename in files:
+                lower = filename.lower()
+                if lower in ("readme.md", "todo.md"):
+                    if filename not in ("README.md", "TODO.md"):
+                        bad_files.append(os.path.join(root, filename))
+
+        msg = (
+            "The following files violate uppercase naming convention "
+            "(must be README.md or TODO.md):\n- " + "\n- ".join(bad_files)
+        ) if bad_files else None
+
+        self.assertEqual(bad_files, [], msg)
+
+if __name__ == "__main__":
+    unittest.main()