diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index 4a3992a..936ff55 100644
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -2,8 +2,10 @@
 name: 'Release'
 
 on:
-  push:
-    branches: [master]
+  workflow_run:
+    workflows: ["pre-commit"]
+    types:
+      - completed
 
 jobs:
   release:
diff --git a/tests/find_dupes b/tests/find_dupes
new file mode 100755
index 0000000..b269ef1
--- /dev/null
+++ b/tests/find_dupes
@@ -0,0 +1,26 @@
+#!/usr/bin/env python3
+#
+"""Check the compiled lscolors.sh file for duplicate extensions."""
+import sys
+import re
+from collections import Counter
+
+
+def main() -> int:
+    with open("../lscolors.sh", "r") as f:
+        data = next(f)
+
+    extensions = re.findall(r"\*\.(.*?)=", data)
+
+    if duplicates := [ext for ext, count in Counter(extensions) if count > 1]:
+        print(f"Duplicates found: {', '.join(duplicates)}")
+        return 1
+    else:
+        print("No duplicates found.")
+        return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())
+
+# EOF
diff --git a/tests/no_dupes b/tests/no_dupes
deleted file mode 100755
index 3b5826f..0000000
--- a/tests/no_dupes
+++ /dev/null
@@ -1,8 +0,0 @@
-#!/usr/bin/env bash
-#
-
-exts="$(dircolors LS_COLORS | head -n1 | sed 's/=[^:]*//g ; s/:/\n/g')"
-exts_sorted="$(sort <<< "$exts")"
-exts_uniq="$(sort -u <<< "$exts")"
-
-diff --color=auto --text --report-identical-files <(echo "$exts_uniq") <(echo "$exts_sorted")