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Demo case file · System design

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Software Engineer

Technology System design Hard 45 min

This is a demo case file: a realistic example written from commonly known interview formats, not a real candidate's interview experience.

Questions asked

  1. Design a URL-shortening service.
  2. How would you scale it to handle 100 million requests a day?
  3. Walk through your database choice and caching strategy.

What to expect

Whiteboard-style. Wanted a high-level architecture sketched in the first five minutes, then went deep on one component of my choosing. Pushed hard on trade-offs — every choice got a "why not X instead?"

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