Building a Replay-Safe Webhook Event Gateway

Webhooks look simple at first: receive an HTTP request, forward it somewhere, return 200 OK. That simplicity disappears the moment the system becomes production-critical. Providers retry. Consumers fail. Payloads arrive twice. Teams need to debug what happened yesterday. A single endpoint becomes dozens of integrations, each with its own routing, retry, transformation, and observability needs. At that point, webhooks stop being “just HTTP callbacks” and become an event gateway problem. This is t