diff --git a/packages/core/src/postgres/migrations/0006_project_ownership.sql b/packages/core/src/postgres/migrations/0006_project_ownership.sql
index 9a1bb6589d..97f745d6ac 100644
--- a/packages/core/src/postgres/migrations/0006_project_ownership.sql
+++ b/packages/core/src/postgres/migrations/0006_project_ownership.sql
@@ -42,14 +42,19 @@ BEGIN
     PostgreSQL roles are cluster-wide while Gate databases apply this migration
     concurrently. Advisory locks are database-local, so make CREATE ROLE itself
     race-safe across databases by accepting the concurrent winner.
+
+    FNXC:ProjectDataIsolation 2026-07-15-01:50:
+    Always CREATE ROLE (no IF NOT EXISTS). The check-then-create path is not atomic
+    across databases of one cluster: concurrent appliers all observe the role as
+    absent and race on CREATE ROLE, raising 23505 on pg_authid_rolname_index.
+    EXCEPTION WHEN duplicate_object OR unique_violation tolerates losing that race
+    (unique_violation is what the index race actually raises).
     */
-    IF NOT EXISTS (SELECT 1 FROM pg_roles WHERE rolname = 'fusion_runtime') THEN
-      BEGIN
-        CREATE ROLE fusion_runtime NOLOGIN NOSUPERUSER NOCREATEDB NOCREATEROLE NOREPLICATION;
-      EXCEPTION
-        WHEN duplicate_object OR unique_violation THEN NULL;
-      END;
-    END IF;
+    BEGIN
+      CREATE ROLE fusion_runtime NOLOGIN NOSUPERUSER NOCREATEDB NOCREATEROLE NOREPLICATION;
+    EXCEPTION WHEN duplicate_object OR unique_violation THEN
+      NULL; -- concurrent applier created the role first; safe to skip
+    END;
     EXECUTE format('GRANT fusion_runtime TO %I', current_user);
   END IF;
 END $$;