Testing and Quality

You cannot safely replace what you cannot verify. Episodes on tests, incidents, and the confidence to change code.

Tests do a different job in legacy work than in greenfield. You write them before changing existing code, to capture how the system behaves today including the quirks nobody documented. They describe what the code does, not what it should do. Once they exist, refactoring stops being frightening, because the tests tell you the moment behavior changes by accident.

The episodes here work through characterization tests, running old and new implementations side by side, what coverage is and is not worth, and why bad release practices are usually a cultural problem rather than a technical one.

27 episodes · browse the full archive

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