diff --git a/cauldron/db.py b/cauldron/db.py
index c860082..3561283 100644
--- a/cauldron/db.py
+++ b/cauldron/db.py
@@ -100,8 +100,10 @@ class DB:
                     if ver in done:
                         continue
                     cur.execute(sql)
+                    # IGNORE to tolerate the multi-worker boot race where two
+                    # gunicorn workers both bootstrap an empty migrations table
                     cur.execute(
-                        "INSERT INTO schema_migrations (version) VALUES (%s)", (ver,)
+                        "INSERT IGNORE INTO schema_migrations (version) VALUES (%s)", (ver,)
                     )
                     applied.append(ver)
         return applied