System design interview tip: always start with requirements, even if the interviewer seems impatient

by ethereal5617
system design
senior
8
5k

I just finished interviewing at 5 companies and noticed a pattern. Interviewers who seem impatient when you're gathering requirements are actually testing your communication skills.

In one Meta interview, I jumped straight into the design after a brief requirements discussion. The interviewer kept asking "but what about X?" and "did you consider Y?" throughout. I passed, but the feedback mentioned I should have spent more time upfront on requirements.

In contrast, at Stripe I spent 8-10 minutes on requirements and the rest of the interview flowed smoothly because we had a shared understanding of the scope.

My framework now:

  1. Functional requirements (5 min)
  2. Non-functional requirements (3 min)
  3. Capacity estimation (5 min)
  4. API design (3 min)
  5. High-level design (5 min)
  6. Deep dive (15 min)
  7. Trade-offs and follow-ups (remaining time)

Has anyone else noticed this pattern?


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