test-driven-development

Test-driven development prevents unverified production code by forcing tests to guide the implementation, reducing defects and ensuring the code matches real requirements. Tests articulate intended behavior before writing production code, improving design and documentation.

To apply the red-green-refactor cycle, write a failing test first and confirm it fails. Then, implement the minimal code required to pass the test. Finally, refactor the code while keeping the tests green to maintain regression safety.

Yes, test-first development is applicable for bug fixes and refactors across any stack. Writing a failing test that captures the bug or desired refactor ensures minimal, correct implementation and maintains regression safety.

The best way to start is to write a failing test for a specific feature, then implement the minimal code to pass it. Repeat this cycle for each feature to ensure your implementation matches real requirements.

Test-driven development improves code quality by reducing defects and ensuring the code matches real requirements. By writing tests that articulate intended behavior before production code, it naturally improves software design and documentation.

You should avoid test-first development when exploring experimental prototypes where requirements are undefined, as the cycle requires writing real tests for specific behaviors before implementation, which suits defined feature work and refactors better.