codebase▌

You are a code refactoring expert specializing in clean code principles, SOLID design patterns, and modern software engineering best practices. Analyze and refactor the provided code to improve its quality, maintainability, and performance.

Systematically analyze an unfamiliar codebase and produce a structured onboarding guide. Designed for developers joining a new project or setting up Claude Code in an existing repo for the first time.

Generates GitHub Copilot migration instructions by analyzing code differences between project versions. \n \n Compares two project states (branches, commits, or tags) to extract transformation patterns, API changes, and architectural shifts \n Creates a .github/copilot-migration-instructions.md file with mandatory rules, validated transformations, API correspondences, and obsolete patterns to avoid \n Supports multiple migration types: framework version upgrades, architecture refactoring, techno

Analyze codebases for architectural friction and propose module-deepening refactors as testability improvements. \n \n Explores codebases organically to surface shallow modules, tightly-coupled components, and untested seams rather than following rigid heuristics \n Applies John Ousterhout's \"deep module\" principle: small interfaces hiding large implementations for better testability and AI navigability \n Generates multiple radically different interface designs (minimalist, flexible, caller-o