winkle
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Backend · expert

Postgres

Schema design, indexing strategy, query optimization, isolation levels, and replication. Includes a live SQL block.

Start interview~ 40 min · 8 questions

What to expect

  1. 1

    Pre-flight (~ 1 min)

    Quick selfie + mic/camera/network check. Same setup as every other Winkle interview.

  2. 2

    Conversation (~ 25–35 min)

    Winkle asks questions one at a time, in your language. She probes weak answers with one follow-up, then moves on.

  3. 3

    Coding block (~ 10 min)

    A small live coding task in a built-in editor. You explain your reasoning as you go.

  4. 4

    Verdict in ≤ 30 seconds

    Winkle writes a scoring artifact: 8 per-question scores, strengths, concerns, and a verdict. You see it instantly.

Sample question

Walk through how you'd identify and fix a slow query in a 10M-row table.

Topics covered

IndexesEXPLAINIsolation levelsJSONBReplication

Before you start

  • Find a quiet space. Wired audio if you have it.
  • Good lighting on your face. Avoid backlight.
  • You can take the interview in any of 8 languages.
  • Block 40 minutes. There's no pause button.

Why this matters

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