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working-with-legacy-code

100 / 100 · Low risk

Fine to try.

By wondelai/skills (GitHub) · coding · 2,667 stars · scanned at commit d8d5d75

Safely change and test untested codebases using Feathers' "Working Effectively with Legacy Code". Use when the user mentions "legacy code", "no tests", "untested codebase", "how do I test this", "seams", "characterization tests", "golden master", "sprout method", "afraid to change this code", "monster method", "dependency breaking", or "inherited a messy codebase". Also trigger when changing code without tests safely, getting a class under test when constructors, statics, or singletons block it…

Works with any agent that supports SKILL.md skills.

What this skill can do

We found nothing in the files we read that matches our rules. That does not prove the skill is safe: see the limits of static scanning.

Other copies in this repository

wondelai/skills has 2 more folders with a skill named working-with-legacy-code. This page shows the lowest-scoring copy.

• plugins/wondelai-skills/skills/working-with-legacy-code 100/100 · Low risk
• plugins/code-craftsmanship/skills/working-with-legacy-code 100/100 · Low risk

Install

Paste this into your terminal. It downloads exactly the version we scanned, not whatever is newest.

if [ -e ~/.agents/skills/'working-with-legacy-code' ] || [ -L ~/.agents/skills/'working-with-legacy-code' ]; then echo 'A skill folder named working-with-legacy-code already exists — not replacing it' >&2; false; else d=$(mktemp -d) && git clone --quiet --filter=blob:none --no-checkout 'https://github.com/wondelai/skills' "$d" && git -C "$d" checkout --quiet 'd8d5d75f83da9f16d8aad5bab5f5b341a4770a30' -- 'working-with-legacy-code' && mkdir -p ~/.agents/skills && cp -R "$d"/'working-with-legacy-code' ~/.agents/skills/'working-with-legacy-code' && rm -rf "$d"; fi

Codex reads ~/.agents/skills directly. For Claude Code, Cursor, Copilot, Gemini CLI, Antigravity or OpenCode, also link it. For Claude Code: ln -s ~/.agents/skills/'working-with-legacy-code' ~/.claude/skills/'working-with-legacy-code' (other agents: ~/.cursor/skills, ~/.copilot/skills, ~/.gemini/skills, ~/.gemini/config/skills, ~/.config/opencode/skills). Or install through the finder skill, which does both.

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Score history