Lessons

1Investigate the payment that appears twice60 min read

Use a short trace to separate duplicated delivery from duplicated business effect.

  • →Turn an incident report into competing hypotheses
  • →Choose a discriminating observation
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2Review a patch as a future operator60 min read

Produce a concise review that ranks correctness, access control, and performance risks.

  • →Review changes by user impact
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3Design one path before scaling the diagram60 min read

Defend a reservation service with a clear invariant, capacity estimate, and failure boundary.

  • →Explain a bounded architecture with explicit guarantees
  • →Revise a design when a constraint changes
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4Defend the result, including its limits60 min read

Present a work sample with a reproducible result, known gaps, and a justified next step.

  • →Defend an implementation using measured evidence
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Skills in this course

  1. 01Turn an incident report into competing hypothesesTurn an incident report into competing hypotheses.
  2. 02Choose a discriminating observationChoose a discriminating observation.
  3. 03Review changes by user impactReview changes by user impact.
  4. 04Explain a bounded architecture with explicit guaranteesExplain a bounded architecture with explicit guarantees.
  5. 05Revise a design when a constraint changesRevise a design when a constraint changes.
  6. 06Defend an implementation using measured evidenceDefend an implementation using measured evidence.