domains / families / software-engineering / legacy-modernizer

legacy-modernizer

combined

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. Refactor legacy codebases, migrate outdated frameworks, and

When to use

• Working on legacy modernizer tasks or workflows
• Needing guidance, best practices, or checklists for legacy modernizer
• Migrating a confirmed legacy runtime/framework or dependency while preserving actual public behavior.
• Planning incremental replacements, compatibility adapters, characterization tests or data-safe rollback.

When not to use

• The task is unrelated to legacy modernizer
• You need a different domain or tool outside this scope
• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.

Skill page

Conflict

The three copies overlap on the core strangler-fig, test-first, feature-flag, and rollback approach, but they disagree on scope and add material steps the others lack. Jeffallan/claude-skills provides a detailed 5-step workflow with validation checkpoints, dependency mapping, 80% coverage targets, and code templates. rmyndharis/antigravity-skills adds specific framework migration examples (jQuery→React, Java 8→17, Python 2→3) and a focus on stored procedure to ORM migration. sickn33/agentic-awesome-skills explicitly corrects the others by stating that database migration should only be done when justified and that a monolith does not automatically need microservices, which conflicts with the broader scope of the other two. Crowning one copy would hide these real alternatives and the specific constraints in the third.