Timed mock · System Design

Design a URL Shortener

45 minutes, split the way the real round is. Answer first, then compare.

Interview clock45:00

Clarify 5mDesign 20mTrade-offs 10mFollow-ups 10m

The interviewer says

Design a system like bit.ly that takes a long URL and returns a short alias. The system should redirect users to the original URL when they visit the short link. Estimate the system handles 100M new URLs per day and 10B redirects per day.

1. Clarify · 5 min
2. Design · 20 min
3. Trade-offs · 10 min
4. Follow-ups · 10 min

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