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Webhook delivery, retries and failures, with sources.

September 21, 202612 min read
What is a webhook? How webhooks work, and the six ways they break in production
A webhook is an HTTP POST one system sends another when something happens. Receiving one is easy. Receiving each one exactly once, verified, in an order you can use, is the actual job — here is how it works, and the six ways it breaks.
September 20, 202615 min read
The transactional outbox, or how Railhook never loses an event it has accepted
Your service gets a 201, and the pod that sent it is OOM-killed four milliseconds later. This is how Railhook still delivers that event, how close it gets to exactly-once, and the one step no sender can take on its own.
September 19, 20268 min read
What Stripe, GitHub and Shopify actually do when your endpoint is down
Three providers, three completely different answers. One keeps trying for three days, one gives up before your pager has finished buzzing, and one deletes your subscription.

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