diff --git a/src/core/app.py b/src/core/app.py
index 8a93de2..2cd1f45 100644
--- a/src/core/app.py
+++ b/src/core/app.py
@@ -32,7 +32,7 @@ def update_pronouns() -> Tuple[str, int]:
     trigger_update_pronouns(pronouns)
     return pronouns, 200
 
-def main():
+def main() -> None:
     app.run(host="0.0.0.0", port=8080)
 
 if __name__ == "__main__":