Python · Senior · System design

Design how a high-load Python service using SQLAlchemy works with PostgreSQL: dozens of instances, each with several workers. How would you organize the connection pools and the session lifecycle?

~10 min by voice

How to approach it

The interviewer checks whether the candidate understands that PostgreSQL connections are a limited and expensive resource in a distributed system, and whether they can calculate the connection budget, manage pools correctly in a multi-process environment, and handle the SQLAlchemy session lifecycle, including the async specifics.

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Topics

sqlalchemy orm

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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