Common mistakes in applying TDD. Recognize the patterns that signal your tests need attention.

Mocks, stubs, fakes — what to use when. Learn to isolate units and break tight coupling in your tests.

SOLID principles made simple. Understand how each principle shapes testable, maintainable code.

How to identify your next refactoring. Prioritize changes that deliver the most design improvement.

Builders, Object Mothers, and Scenario Factories. Turn test setup into a composable, domain-language API agents and humans can read.

Keep the language of the business, the code, and the tests converged. A practical guide to stopping vocabulary drift.