test-driven-development

The red-green-refactor cycle in test-driven development involves writing a failing test, implementing minimal code to make it pass, and then safely refactoring while maintaining a green baseline. This enforces test-first development to prevent production code without validated expectations.

To start writing failing tests for feature implementation, write a test defining the desired behavior, run it to confirm it fails, then implement the minimal production code needed to satisfy that test and pass the validation.

You should use test-first development for bug fixes and refactoring whenever you need to prevent regressions and increase confidence during maintenance. It requires automated failing tests to drive implementation changes across the codebase.

The best way to ensure minimal production code and avoid over-engineering is to write tests first and implement only what is needed to satisfy them. This test-driven approach restricts production code strictly to validated expectations.

Yes, you can apply test-driven development across different codebases and engineering teams. It guides engineers on when to write tests, run them, and implement minimal code, maintaining a verified green baseline universally.