Legacy Code Pack for Claude Code

Five skills that make Claude Code careful in code nobody fully understands anymore. It maps the repo, pins down what the code does today with tests, and then refactors, upgrades and deletes in small steps you can check.

$4.99one-time, VAT included where it applies Buy now for $4.99 Or get all 7 kits for $9.99

Instant download: a zip with 5 skills, a setup guide and an example ONBOARDING.md. The $9.99 bundle gets you all 7 kits (35 skills). Free updates. 14-day refund, no questions asked.

What's inside

Skill	What it does
`map-codebase`	Explores an unfamiliar repo and writes an `ONBOARDING.md`: architecture, entry points, request flows traced hop by hop with file and line, how to run and test it, and the risky areas, with evidence.
`characterize`	Writes characterization (golden-master) tests that pin what the code does today, odd behavior included. Labels suspected bugs instead of fixing them, and mutates the code to prove the tests can fail.
`refactor-safely`	Refactors in small behavior-preserving steps. Runs the tests after every step, commits each one separately, and stops and reports if behavior changes.
`upgrade-dependency`	Handles a major-version upgrade: reads the migration guide, finds every affected call site, upgrades in separate commits and fixes what breaks, with the tests run at each step.
`remove-dead-code`	Finds unused exports, files, flags, endpoints and dependencies with evidence and a confidence level. Removes only the safe ones in one revertable commit and lists the rest for you to decide.

What a dead code report looks like

Example output from remove-dead-code on a mid-sized TypeScript service:

Removed (High, commit 4be21d0): 12 items, -640 lines, tests 301/301 green.

src/utils/legacyCsv.ts
File. Nothing imports it; the last import was removed in 2023-04 (git log -S).

formatPhoneOld()  src/fmt.ts:88
Only reference was its own test. Both removed.

For a human to decide:

POST /api/v1/export  [Medium]
No client in the repo calls it, but it's a public route.
Confirm: check access logs for the last 30 days.

ENABLE_NEW_CART  [Low]
Always true in config/prod.yml, but the flag service may override it.
Confirm: check the live flag value, then inline the true branch.

Requirements

Claude Code, with any plan or API key that runs it.
A git repo. Any language or framework: the skills use your project's own build and test commands.
Optional: standard analysis tools such as knip, vulture or staticcheck, which remove-dead-code uses when they're available.

Install in two minutes

unzip legacy-code-pack-1.0.0.zip
mkdir -p ~/.claude/skills
cp -R legacy-code-pack/skills/* ~/.claude/skills/

Then say "map this codebase" in any repo.

License

Use and modify the skills in your own projects and inside your company, including in private repos. You can't resell or redistribute them. Full terms.