diff --git a/scripts/check-message-compatibility.py b/scripts/check-message-compatibility.py
index c141103..5af4c6e 100755
--- a/scripts/check-message-compatibility.py
+++ b/scripts/check-message-compatibility.py
@@ -150,8 +150,8 @@ def main(repo1: str, repo2: str, verbose: bool = False):
     else:
         if verbose:
             for msg_type in incompatible_types:
-                file1 = f'{repo1}/msg/{msg_type}.msg'
-                file2 = f'{repo2}/msg/{msg_type}.msg'
+                file1 = os.path.join(repo1, 'msg', f'{msg_type}.msg')
+                file2 = os.path.join(repo2, 'msg', f'{msg_type}.msg')
                 compare_files(file1, file2)
             print("Note: The printed diff includes all content differences. "
                   "The computed check is less sensitive to formatting and comments.", end='\n\n')