Webhook Idempotency: How to Handle Duplicate Events Without Breaking Your System
2026-07-22
#webhooks, #engineering, #best-practices
Why Duplicate Webhooks Are Inevitable
Every major webhook provider uses at-least-once delivery semantics. Duplicates are a feature, not a bug.
What Happens Without Idempotency
Multiple charge records, duplicate emails, inflated metrics, race conditions.
The Core Pattern: Event ID Deduplication
Use a processed-events table with atomic INSERT to gate processing.