Your question is Webhooks in JavaScript. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Explain what a webhook is and how they function in a web application, including how you would handle incoming webhook events in JavaScript.
Cover the sender, HTTP request lifecycle, payload validation, authentication or signature verification, response status, retries, and asynchronous processing. Use a JavaScript server example such as an Express route, and explain how you would prevent duplicate event processing.
Scope: server-side JavaScript and HTTP webhooks; no provider-specific implementation is required.