Bitrot
ELI5 — The Vibe Check
Bitrot is when code that worked perfectly six months ago mysteriously stops working. Nobody changed it. The world changed around it — OS update, dep bump, API deprecation. It rotted in place.
Real Talk
Bitrot (software rot) is the gradual degradation of software quality or functionality over time, despite no changes to the code itself. Causes include evolving runtime environments, dependency updates, API deprecations, and ecosystem drift. Prevention: regular dependency updates, integration tests in CI, and automated canary builds.
When You'll Hear This
"The cron script bitrotted — Node 24 broke it." / "Untouched code bitrots faster than you'd think."
Related Terms
Code Rot
Code rot is the slow decay of a codebase from neglect. Comments become lies. Dead code piles up. Conventions drift.
Dependency
A dependency is a package your project relies on to work. Your app depends on React to render UI, axios to make requests, and dotenv to read config.
Legacy Code
Old code that nobody wants to touch but everyone depends on.
Technical Debt
Technical debt is the coding equivalent of putting things on a credit card.