> Webhooks are the most common way to receive signals from external systems, but processing them safely is not trivial

I see webhooks documented all the time, but I have yet to use them in practice, nor have my customers requested them. Is the above not true, or are they widely used in some sectors and not others?

In payment gateway integration, webhooks are usually considered a single source of truth for updating the payment status, with status check api as a fallback.

They are indeed everywhere, but it's possible you don't have a need for them. For example, every time you buy something online using Stripe, the seller receives a webhook indicating that a purchase was completed.

I receive webhooks all the time as ack that something was processed/ or a notification of the status of some sort of thing in an external system that we don't control.