Working Effectively with Legacy Code Skill
SkillAI & modelsApply Michael Feathers-inspired legacy-code rules when changing hard-to-test code safely with characterization tests, seams, sprout methods, or wrap methods.
Available today. Use it from your connected AI after setup.
No other account needed.
Connect ahel once, and every AI you use reads what you have installed.
Then ask your AI: use the Working Effectively with Legacy Code Skill skill
What this skill tells your AI
The instructions your AI receives, as published by ciembor/agent-rules-books in working-effectively-with-legacy-code/SKILL.md and read by ahel’s review.
Use this skill when a task involves risky legacy changes, missing tests, characterization tests, seams, dependency breaking, sprout method, wrap method, or incremental risk reduction.
Before making design or code decisions, read and apply working-effectively-with-legacy-code.mini.md. Use working-effectively-with-legacy-code.md only as a deeper reference when the mini rules are not enough for the current legacy-code tradeoff.
Signals
- GitHub stars
- 3k
- Forks
- 489
- Last commit
- Sep 2026
Advanced
- Catalog kind
- skill
- Gateway key
working-effectively-with-legacy-code- Source
- github.com/ciembor/agent-rules-books