diff --git a/src/lightning_hivemind/strategy.py b/src/lightning_hivemind/strategy.py
index 04b7ec3..7fcddd3 100644
--- a/src/lightning_hivemind/strategy.py
+++ b/src/lightning_hivemind/strategy.py
@@ -149,7 +149,7 @@ def __init__(
         bootstrap_timeout: Optional[float] = None,
         use_relay: bool = True,
         use_auto_relay: bool = False,
-        identity_path: str = None,
+        identity_path: Optional[str] = None,
         **optimizer_kwargs: Any,
     ):
         if platform.system() != "Linux":