Backend · Senior · System design

Checkout involves three services, orders, payments and inventory, and each has its own database. How do you keep the data consistent if one of the steps fails?

~10 min by voice

How to approach it

The interviewer checks whether the candidate understands how to keep services consistent without a distributed transaction. What matters is whether they can design a saga that survives failures: with idempotency, reliable command delivery, the right order of steps, and a plan for when a rollback fails.

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Answers0

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Topics

distributed systems saga

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Answer by voice

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 · ~10 min