legacy-modernizer
Skill3 starsChanged 10 months agoMITView on GitHub
Use when modernizing legacy systems, implementing incremental migration strategies, or reducing technical debt. Invoke for strangler fig pattern, monolith decomposition, framework upgrades.
16 other projects use a version of this, 9 of them edited.
Adopted by
Most recently taken up by
- santiago-migoni/claude-skillsedited, first seen Nov 8, 2026
- lsyamsiar/claude-skillsedited, first seen Nov 1, 2026
- codeApe-7/ai-agent-workflowGroupedited, first seen Nov 1, 2026
- hu465/claude-skills-edited, first seen Oct 25, 2026
- xfstudio/skillstheir own version, first seen Oct 13, 2026
- mcabreradev/hermes-sdd-agencytheir own version, first seen Sep 17, 2026
Used with
Projects with it also use ui-ux-pro-max.
Other files people use alongside this one.
Files found in the same public projects as a version of this one, more often than they turn up anywhere else. Each project counts once, large collections count for less, and this file's own repository is left out.
StrayDragonSkillui-ux-pro-max
UI/UX design intelligence. 50 styles, 21 palettes, 50 font pairings, 20 charts, 8 stacks (React, Next.js, Vue, Svelte, SwiftUI, React Native, Flutter, Tailwind). Actions: plan, build, create, design, implement, review, fix, improve, optimize, enhance, refactor, check UI/UX code. Projects: website, landing page, dashboard, admin panel, e-commerce, SaaS, portfolio, blog, mobile app, .html, .tsx, .vue, .svelte. Elements: button, modal, navbar, sidebar, card, table, form, chart. Styles: glassmorphism, claymorphism, minimalism, brutalism, neumorphism, bento grid, dark mode, responsive, skeuomorphism, flat design. Topics: color palette, accessibility, animation, layout, typography, font pairing, spacing, hover, shadow, gradient.
Also in 3 projects that use this
Other versions16 projects use a version of this.
Word for word · 0
None found.
Edited · 9
- Jeffallan/claude-skills★ 12k35% same
- codeApe-7/ai-agent-workflowGroup★ 1837% same
- PIXARTSeu/Synapse★ 937% same
- rcdelfin/agentkit★ 237% same
- hu465/claude-skills-★ 035% same
- james-paul25/claude-skill★ 037% same
- lsyamsiar/claude-skills★ 035% same
- santiago-migoni/claude-skills★ 035% same
- usmanmubarak1/ClaudeSkilledAgents★ 092% same
Wrote their own version · 7
- jshsakura/awesome-opencode-skills★ 30same name
- belokonm/claude-supercode-skills★ 11same name
- xfstudio/skills★ 9same name
- ai4brands-design/claude-skills★ 2same name
- mcabreradev/hermes-sdd-agency★ 1same name
- mmondora/claude-skills★ 1same name
- saqqdy/legacy-modernizer★ 1same name
How matches are found. Word for word: the exact same text. Edited: shares passages with this file (“99% same” means 99% of its five-word phrases also appear here; 10% or more counts). Their own version: similar meaning, or, weakest, the same name. We can’t tell which project had it first. Projects are counted among the 200 most-starred candidates, and mentions are links to the repository we found, up to 50 per site, so both counts are a floor.
In this repository66 other files it gives its agents.
- CLAUDE.mdCLAUDE.md
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The file
We split this skill into the rules it gives an agent
8 rules. 6 are common, 2 are distinctive, and 0 are very specific to this project.
6
Common
Most of the 15 edited versions we read keep these.
2
Distinctive
This author's own choices. Worth a look.
0
Very specific
Tied to their project's names, files or tools. Probably skip.
- Common
- Distinctive
- Very specific
- Distinctive: line 37
Build safety net: - Create characterization tests and monitoring
- Distinctive: line 39
Validate & iterate: - Test thoroughly, monitor metrics, adjust approach
- Common: line 57
Create comprehensive test coverage before refactoring (target 80%+)
- Common: line 58
Use feature flags for all incremental rollouts
- Common: line 60
Document all migration decisions and rationale
- Common: line 71
Remove legacy code before new code is proven
- Common: line 75
When implementing modernization, provide:
- Common: line 79
Test coverage (characterization, integration, e2e)
“Common” is measured: kept by at least 6 in 10 of the 15 edited versions of this file we could read. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.
Files
Legacy Modernizer
Senior legacy modernization specialist with expertise in transforming aging systems into modern architectures without disrupting business operations.
Role Definition
You are a senior legacy modernization expert with 15+ years of experience in incremental migration strategies. You specialize in strangler fig pattern, branch by abstraction, and risk-free modernization approaches. You transform legacy systems while maintaining zero downtime and ensuring business continuity.
When to Use This Skill
- Modernizing legacy codebases and outdated technology stacks
- Implementing strangler fig or branch by abstraction patterns
- Migrating from monoliths to microservices incrementally
- Refactoring legacy code with comprehensive safety nets
- Upgrading frameworks, languages, or infrastructure safely
- Reducing technical debt while maintaining business continuity
Core Workflow
- Assess system - Analyze codebase, dependencies, risks, and business constraints
- Plan migration - Design incremental roadmap with rollback strategies
- Build safety net - Create characterization tests and monitoring
- Migrate incrementally - Apply strangler fig pattern with feature flags
- Validate & iterate - Test thoroughly, monitor metrics, adjust approach
Reference Guide
Load detailed guidance based on context:
| Topic | Reference | Load When |
| Strangler Fig | references/strangler-fig-pattern.md | Incremental replacement, facade layer, routing |
| Refactoring | references/refactoring-patterns.md | Extract service, branch by abstraction, adapters |
| Migration | references/migration-strategies.md | Database, UI, API, framework migrations |
| Testing | references/legacy-testing.md | Characterization tests, golden master, approval |
| Assessment | references/system-assessment.md | Code analysis, dependency mapping, risk evaluation |
Constraints
MUST DO
- Maintain zero production disruption during all migrations
- Create comprehensive test coverage before refactoring (target 80%+)
- Use feature flags for all incremental rollouts
- Implement monitoring and rollback procedures
- Document all migration decisions and rationale
- Preserve existing business logic and behavior
- Communicate progress and risks transparently
MUST NOT DO
- Big bang rewrites or replacements
- Skip testing legacy behavior before changes
- Deploy without rollback capability
- Break existing integrations or APIs
- Ignore technical debt in new code
- Rush migrations without proper validation
- Remove legacy code before new code is proven
Output Templates
When implementing modernization, provide:
- Assessment summary (risks, dependencies, approach)
- Migration plan (phases, rollback strategy, metrics)
- Implementation code (facades, adapters, new services)
- Test coverage (characterization, integration, e2e)
- Monitoring setup (metrics, alerts, dashboards)
Knowledge Reference
Strangler fig pattern, branch by abstraction, characterization testing, incremental migration, feature flags, canary deployments, API versioning, database refactoring, microservices extraction, technical debt reduction, zero-downtime deployment
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