What problem does it solve? Refactoring untested legacy code is risky because there is no way to detect behavior changes or roll back safely. This Skill builds a complete safety net before any surgery begins, capturing current behavior in tests and creating recovery points. ## Core Features & Use Cases - Characterization Tests: Writes tests that capture what the code currently does, including existing bugs, so any behavior change during refactoring is detected. - Boundary Markers & Config Freeze: Adds @legacy, @do-not-touch, and @bridge comments to source files and snapshots config files (tsconfig, ESLint, lockfiles) into .rune/ for baseline comparison. - Git Rollback Point: Creates a tagged commit (rune-safeguard-<module>) so any failed refactoring can be reverted instantly. - Use Case: Before refactoring a legacy payment module with no tests, run this Skill to generate characterization tests covering all public functions, freeze the config, and tag a rollback point — then proceed with surgery only after all tests pass on the unmodified code. ## Quick Start Use the rune-safeguard skill to build a safety net with characterization tests and a rollback tag for the billing module before I refactor it.
