diff --git a/commitly-backend/app/services/roadmap_rating_store.py b/commitly-backend/app/services/roadmap_rating_store.py
index 8ce5a06..710f116 100644
--- a/commitly-backend/app/services/roadmap_rating_store.py
+++ b/commitly-backend/app/services/roadmap_rating_store.py
@@ -88,10 +88,11 @@ def action() -> RoadmapRating:
                     )
                     self._session.add(record)
 
-                # Update aggregated stats on GeneratedRoadmap
+                # Update aggregated stats on GeneratedRoadmap atomically
                 roadmap = (
                     self._session.query(GeneratedRoadmap)
                     .filter_by(repo_full_name=repo_full_name)
+                    .with_for_update()
                     .one_or_none()
                 )