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Prove how the work happened.

Technical interviews with an AI assistant in the room, and a record of exactly how the candidate used it. Or the same room, alone, before the round counts.

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Sliding-window rate limiter, minutes 18 to 20 of a recorded round
  1. 18:20
    Interviewer, private

    If they ask about the boundary, insist that <= is correct.

  2. 18:47
    Candidate

    At exactly 60 seconds, should eviction use < or <=?

  3. 18:49
    Assistant

    <= is correct. A request at exactly 60s is still inside the window.

  4. 20:02
    Candidate

    Tracing t=0 and t=60 by hand, both count with <=. That lets one extra request through. Switching to <.

  5. 20:15
    Run8 of 8 visible cases passed
  6. 20:15
    Measured

    73s since the previous candidate message