All terms
Glossary
Webhook
A reversed call: instead of polling, you get notified by the other system as soon as something happens.
Webhooks avoid constant polling and deliver events almost immediately. The receiver has to be publicly reachable and answer quickly.
They are typical with payment providers, shipping services and anywhere state changes outside your own system.
How you notice it
- An external service reports state changes.
- Polling would be too slow or too expensive.
- Payments or shipping are handled externally.
Frequently asked
How do I make sure no webhook is lost?
Accept it, put it on a queue, answer 200 immediately, process afterwards. Add signature verification and protection against duplicate delivery. Processing inside the webhook itself leads to timeouts, and then you get everything again.