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API Development Quiz Practice
Active Recall Drill Session
← Exit Session
Question 1 of 1
medium
API Development
Why is a webhook handler that credits a user's balance on every payment.succeeded event, with no deduplication, described as guaranteed to eventually double-credit, not just theoretically at risk?
A
It's actually very unlikely to ever happen in practice
B
Because at-least-once delivery is the DOCUMENTED, expected behavior of webhook systems — duplicate delivery isn't a rare edge case, it's a predictable and eventual consequence of the delivery model itself
C
Because webhooks always deliver every event exactly twice
D
This only happens if the receiving server has a bug
Check Answer