Webhook

A webhook is a mechanism that allows an API or service to push data to your application automatically when a specific event occurs, rather than requiring you to poll an endpoint repeatedly.

When an event triggers, the server sends an HTTP POST request to a URL you have registered. Webhooks are the foundation of event-driven architectures - instead of checking every minute whether a property price changed, a webhook delivers the update instantly when it happens.

Implementing a webhook listener requires exposing a public URL endpoint that accepts POST requests, validates the payload, and processes the event. Most webhook providers include a signature in request headers so you can verify authenticity.