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working-effectively-with-legacy-code

by agent-rules-books

Apply Michael Feathers-inspired legacy-code rules when changing hard-to-test code safely with characterization tests, seams, sprout methods, or wrap methods.

v1.0.0New

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Install this skill

Run this command in your terminal. No account required — it auto-detects your AI tool and installs the skill file.

npx @skills-hub-ai/cli install agent-rules-books-working-effectively-with-legacy-code
Or download directly:
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Setup by platform

Claude Code

~/.claude/skills/<skill>/SKILL.md

Setup guide →

Install

One-click setup for your editor

Run in your project root

npx @skills-hub-ai/cli install agent-rules-books-working-effectively-with-legacy-code --target claude-code
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Frequently asked questions about working-effectively-with-legacy-code

What does the working-effectively-with-legacy-code skill do?

Apply Michael Feathers-inspired legacy-code rules when changing hard-to-test code safely with characterization tests, seams, sprout methods, or wrap methods. It's a reusable SKILL.md instruction set that loads into your AI coding assistant on demand, no prompt engineering, no copy-pasting every session.

How do I install the working-effectively-with-legacy-code skill?

Run `npx @skills-hub-ai/cli install agent-rules-books-working-effectively-with-legacy-code` from your terminal. The CLI writes the SKILL.md to the correct location for your AI tool (e.g. ~/.claude/skills/agent-rules-books-working-effectively-with-legacy-code/ for Claude Code or ~/.cursor/skills/ for Cursor with --target cursor) and adds it to your project's .skills.json lockfile.

Which AI tools does working-effectively-with-legacy-code work with?

working-effectively-with-legacy-code runs in Claude Code. It follows the open Agent Skills standard (SKILL.md), so the same skill works in every supported tool without modification.

Is the working-effectively-with-legacy-code skill free?

Yes. Every skill on skills-hub.ai is free and open-source. There are no premium tiers, paywalls, or usage limits. You only pay for whatever AI assistant you're already using.

How do I use working-effectively-with-legacy-code after installing it?

In Claude Code, type `/agent-rules-books-working-effectively-with-legacy-code` (or whatever slash command the skill registers) and the AI follows the skill's instructions immediately. You can also reference it by name in natural language, your AI loads the skill into context when relevant.

Can I share the working-effectively-with-legacy-code skill with my team?

Yes. Commit your project's .skills.json lockfile and teammates run `npx @skills-hub-ai/cli install` (no args) to install every skill at the exact version you pinned. Organization-scoped installs work via skills-hub.ai organizations.