architecture Designing a Webhook Delivery System: Why Your Retries Need an Idempotency Key josedacruz, September 13, 2026September 13, 2026 TL;DR: A webhook is just an HTTP POST your system sends to someone else’s server when something happens, but “just an HTTP POST” hides a lot of hard problems. Networks drop packets, receivers time out, and retries create duplicates — so a webhook delivery system that actually works needs retries… Continue Reading