Are you fighting against a poorly tested, undocumented legacy codebase? Are deadlines too short to refactor the mess? Imagine cleaning up the codebase as you go. Implement new features without breaking existing behaviour in no time! The " Legacy Code: First Aid Kit " contains 14 techniques to quickly and safely rescue a legacy codebase: Identify Hotspots - Draw Dependency Graphs - The Mikado Method & The Parking - Micro-committing - Exploratory Refactoring - Three Automated Refactorings - Incremental Refactorings - Proximity Refactoring - Decouple Core from Infrastructure - Approval Testing - Subclass & Override - Move Function to Delegate - Wrap & Sprout - Progressive Naming Each move comes with a structure that explains when to use it, how to implement it, why it works, and how to adapt to various situations. With these 14 moves, you will be able to identify what makes code difficult to test, quickly deploy a safety net around it, and clean up messy code while shipping value as you go!