A chart describing a flow over view: Incoming API->DB->Engine A->Engine B->Outgoing API->3rd party->Costumer credit card. The API creates a payment request record with status 0. Engine A verifies it and changes the status to 1. Engine B takes the payment and send it to the 3rd party, and changes the status to 2. Write 5-6 critical defects.
Anoniem
It's essential to demonstrate that you can really go deep... there are plenty of followup questions and (sometimes tangential) angles to explore. There's a lot of Software QA Engineer experts who've worked at Payoneer, who provide this sort of practice through mock interviews. There's a whole list of them curated on Prepfully. prepfully.com/practice-interviews