PROBLEM
Success can still be dangerous.
A provider may retry the same event. Without idempotency, a successful handler can repeat a side effect that should only happen once.
THE LAB · WEBHOOK RELIABILITY
A compact Node/Express project built to demonstrate safer webhook handling with HMAC signature verification, idempotency, automated tests, and CI.
PROBLEM
A provider may retry the same event. Without idempotency, a successful handler can repeat a side effect that should only happen once.
PATTERNS
The project demonstrates request signing, duplicate-event protection, deterministic behavior, and automated verification of the unhappy path.
DEVREL VALUE
The implementation is intentionally small enough to explain clearly, demo live, break on purpose, and use as a reference project.
PAIR IT WITH THE TUTORIAL
Read the companion breakdown on duplicate delivery, signatures, retries, and idempotency.
Read the tutorial →