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Demo case file · Phone screen

Stripe

Backend Engineer

Technology Phone screen Medium 30 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. Implement a basic rate limiter.
  2. Explain how you would design an idempotent API endpoint for processing payments.

What to expect

Short and focused — only two questions in thirty minutes. Had to write actual runnable code in a shared editor, not pseudocode. Cared a lot about edge cases: retries, duplicate requests, partial failures.

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