Test-Driven Development

No production code without a failing test. RED-GREEN-REFACTOR, every time.

Triggers

• User asks to implement a feature, function, or component
• User asks to add behavior to existing code
• Any task that produces production code

HARD GATE: Failing Test Required

Before writing ANY production code, you MUST:

1. Write a test that describes the desired behavior
2. Run the test and show the failure output
3. Only then write the production code

If you catch yourself writing production code first, STOP immediately, delete it, and write the test.