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Paths/Claude Engineer/Testing with Claude Code / Fix the Failure

Challengeadvancedubuntu:24.04Ask AI

Guard the Regression

A bug that came back is a missing test, not bad luck. Write the rule that makes the fix permanent.

Validator

⏱ 0:00

IDLE — checks run live as you type commands; submit when done

01Requirements

live checks
  • File ~/.claude/testing/regressions.md exists○
  • The document states what a fixed bug must leave behind○
  • The document states how the regression is caught before it ships○

02Walkthrough

1 of 4 revealed
  1. 01

    Create the testing directory

    The rule lives with the briefs.

    mkdir -p ~/.claude/testing
  2. 3 locked · each failed submit reveals one

03Stuck?

0 of 3 revealed

Take a hint without losing the lab — each one points at the thing to look at, not at the answer.

04AI Tutor

guides, never solves

Tell me what you're stuck on — I'll nudge, not solve. Which requirement are you looking at?

04Notebook

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learner@lab — ubuntu:24.04

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Read a Failing Test Before Fixing It

Testing with Claude Code

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Set the Permission Set

Keeping Claude Code Safe