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name: legacy-modernizer description: Use when Designs incremental migration strategies, identifies service boundaries, produces dependency maps and migration roadmaps, and generates API facade designs for aging codebases.

Legacy Modernizer

Designs incremental migration strategies, identifies service boundaries, produces dependency maps and migration roadmaps, and generates API facade designs for aging codebases. Use when modernizing legacy systems, implementing strangler fig pattern or branch by abstraction, decomposing monoliths, upgrading frameworks or languages, or reducing technical debt without disrupting business operations. — One of 66 full-stack developer skills in Jeff Allan's claude-skills plugin (MIT, 9.4k stars).

What you get

• Public GitHub repo (Jeffallan/claude-skills)
• the skills/legacy-modernizer folder with SKILL.md and references. Install via /plugin install fullstack-dev-skills@jeffallan.

Customize your output

• Fork the repo and extend the skill's reference files for your own stack conventions.

Example output

Activates on a matching request (e.g. building or reviewing Legacy Modernizer code) and can chain with other skills in the pack.

Best for

Full-stack developers and engineering teams using Claude Code.