Idempotency Beyond API (Application Programming Interface) Requests: A Layered Defense
Idempotency isn't one header. It's a defense stack that has to be built separately across five layers, from the API key down to the step marker.
Webhooks Articles
Posts about webhooks
Webhook Reliability in Payment Systems
Webhooks repeat, disappear, arrive out of order, and show up late. Verify the signature, ACK fast, and never run the heavy work synchronously.
Optimistic Concurrency Under Webhooks
When a webhook and a synchronous response touch the same payment at once, how do a version token and a lease resolve the race — and why can a stale read…