Python · Mid-level · System design

Design an aggregator service in FastAPI: for every incoming request it has to call five external services and build a single response from their replies. How do you keep latency low and stay resilient to failures in those services?

~10 min by voice

How to approach it

They're checking whether you understand FastAPI's async model in practice: whether you can parallelize I/O, cap waiting time, keep one failed service from taking down the whole response, and deploy the service properly for load.

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Topics

asyncio fastapi

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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