QA · Senior · Theory

How would you test a payment creation API for idempotency and concurrent requests?

~4 min by voice

How to approach it

The interviewer wants to see whether you understand that payment idempotency is a guarantee of "one key, one payment, one result", and whether you can prove it with tests under concurrent load and network failures, checking the real state of the system and not just HTTP codes.

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api testing concurrency

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The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min