Skill UI

A comprehensive optimization guide maintained by Vercel, covering 45 rules for React and Next.js. Use this resource when building new components, implementing complex data fetching (client or server-side), refactoring code, or systematically improving bundle size and overall load times for high-performance web applications.

This skill guides developers through modernizing React applications. It covers migrating from class components to functional components using hooks, upgrading React versions, adopting concurrent features (like Suspense), and applying automated refactoring techniques using codemods. It is essential for maintaining high-performance, modern React codebases and integrating TypeScript.

This skill reviews git diffs or specific file scopes for code reuse, quality, efficiency, clarity, and standards compliance. It optionally applies safe, behavior-preserving fixes. It uses parallel read-only sub-agents to inspect code while the main agent applies changes. Suitable for auditing changes, simplifying code, or refactoring.

This skill reviews code differences (diffs) to identify opportunities for improvement in clarity, reusability, efficiency, and overall quality. It employs multiple specialized sub-agents (e.g., Code Reuse, Efficiency, Quality) to audit changes. It can provide high-confidence, behavior-preserving fixes when requested, ensuring the code adheres to best practices without introducing regressions. Best used when refactoring, cleaning up, or auditing a specific code scope.

This skill enforces a high standard for all generated code, prioritizing correctness, clarity, and idiomatic patterns across all languages. It helps minimize code bloat by removing unnecessary abstractions and verbose patterns, while also optimizing the agent's output by using targeted diffs and eliminating excessive conversational overhead. Use this for all code generation, refactoring, or review tasks.

This skill identifies dependencies at heightened risk of exploitation or takeover by evaluating factors like maintainer activity, popularity, and security history. It generates a security report for supply chain attack surface assessment and pre-engagement scoping.

This expert reviews and rectifies complex Swift Concurrency issues, such as actor isolation violations, Sendable safety breaches, and data races. It applies modern patterns (like `@MainActor` and `actor` usage) to ensure code adheres to Swift 6.2+ standards while minimizing behavior changes. Use it when debugging concurrency warnings or migrating legacy codebases.

Write, review, and refactor SwiftUI for iOS or macOS, covering data flow, view composition, performance, identity, environment, localization, animation, API migration, and Instruments traces.

A comprehensive guide detailing how to refactor large, complex SwiftUI views into smaller, more stable, and explicit components. It emphasizes adopting a lightweight state approach (favoring local state and environment variables over excessive view model layers) to improve data flow, readability, and overall code maintainability in modern iOS development.

This skill acts as an expert TDD orchestrator, guiding users through the red-green-refactor cycle and coordinating multi-agent testing workflows. It ensures comprehensive test coverage, enforces best practices, and integrates AI-assisted test generation for modern software development. Suitable for complex projects requiring disciplined testing strategies, continuous integration, and quality assurance across various programming languages and frameworks.

Execute a comprehensive Test-Driven Development (TDD) workflow enforcing the red-green-refactor discipline. This skill guides test-first development through coordinated agent orchestration, covering requirements analysis, unit test creation, implementation, refactoring, and integration testing with strict coverage thresholds.

Safely refactor code with a comprehensive TDD safety net: establish a green baseline, detect code smells, apply design patterns and SOLID principles, optimize performance, and verify all tests remain green.