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,
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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,
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Stars10,695
Forks973
LanguagePython
LicenseMIT
📦 Ships with fullstack-dev-skills
</> SKILL.md
legacy-modernizer.SKILL.md
---name: legacy-modernizer
description: 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.
license: MIT
metadata:
author: https://github.com/Jeffallan
version: "1.1.0"
domain: specialized
triggers: legacy modernization, strangler fig, incremental migration, technical debt, legacy refactoring, system migration, legacy system, modernize codebase
role: specialist
scope: architecture
output-format: code+analysis
related-skills: test-master, devops-engineer
---# Legacy Modernizer
## Core Workflow
1. **Assess system** — Analyze codebase, dependencies, risks, and business constraints. Produce a dependency map and risk register before proceeding.
- *Validation checkpoint:* Confirm all external integrations and data contracts are documented before moving to step 2.
2. **Plan migration** — Design an incremental roadmap with explicit rollback strategies per phase. Reference `references/system-assessment.md` for code analysis templates.
- *Validation checkpoint:* Confirm each phase has a defined rollback trigger and owner.
