Ask HN: How do you test payment webhook edge cases?

[jalalmanafi]

I work at a PSP. We recently had a production bug where a payment succeeded but our system didn't update — the webhook was delayed 45 seconds. Stripe's test mode doesn't simulate delays, timeouts, or webhook failures. We ended up writing internal mocks, but it's tedious. Considering building a simple tool: configurable delays, webhook failure simulation, request timeline. Curious how others handle this. Do you just write custom mocks? Accept the risk? Use something I don't know about?

[kay_o]

proxy that does all of the above rather than mocks. we had configurable one based on txid.

ex: tx uuid fe83dd01-aaaa-aaaa-aaaa-000000005373 if chunk1 is aaaa, then treat last bit as 'delay for 5373ms'

[jalalmanafi]

Clever approach — encoding the behavior in the txid itself.

Did you have a UI to configure scenarios, or was it all code-based? And did you simulate webhook failures/retries too, or just delays?