reliability-concurrency

Preventing race conditions in BullMQ workers requires designing idempotent consumers that survive retries without duplicating side effects. You achieve this by using natural idempotency keys and atomic status updates so overlapping worker executions never corrupt state transitions.

Advisory locks are concurrency controls that ensure only one worker can apply a versioned schema change at a time. You need them for sharded migration runners to prevent multiple workers from executing overlapping database migrations and causing silent data corruption.

To make replace-write operations safe from race conditions, wrap the delete-then-insert workflow in atomic transactions and add race protection. This ensures the full replace operation completes as a single unit, preventing partial overwrites when concurrent workers overlap.

Yes, idempotent status updates are essential for handling concurrent background jobs safely. By ensuring status transitions remain correct even when retried or run by multiple workers at once, you avoid silent data corruption from overlapping job executions.

The best way to handle failures in concurrent database workflows is through loud failure handling rather than silent catches. When race conditions or lock contention occurs, failing loudly prevents silent data corruption and surfaces the exact concurrency issue immediately for resolution.