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Code by Pawpu

Engineering Lab

Incident Desk

A browser incident desk: logs, metrics, traces, database, cache, API, deploys, and changes. Name the root cause. Then read the postmortem.

Loading desk…

How the challenge works

  • Open one channel at a time. You do not need every pane to name the cause.
  • Hot channels usually explain the symptom. Noise channels are there so you practice skipping them.
  • After you name a cause, the desk shows evidence, the fix, the trade-off, and what to monitor. This is a demo incident — not live telemetry.

Key concepts

Acquire time vs query time

If traces spend a second getting a connection and 10ms running SQL, you do not have a slow query. You have a pool problem.

Config is a deploy

A TTL change is a release. Treat it like one: diff, canary, and an abort.

Common mistakes

  • Scaling API boxes because latency is up. Check the pool and the cache first.
  • Reading every channel before forming a hypothesis.

Interview tips

  • Say the symptom in one sentence, then pick the cheapest signal that would falsify it.
  • Name the blast radius and the rollback before you name the elegant fix.

Related challenges

Built by Al Beltran