Frontend

Use when implementing navigation in React Native Web projects. Provides patterns for React Navigation, deep linking, and web-specific routing.

Use when building reusable component patterns with Tailwind CSS. Covers component extraction, @apply directive, and composable design patterns.

Use when implementing Apollo Client patterns for queries, mutations, cache management, and local state in React applications.

Use when managing state and side effects in Ink applications using React hooks for terminal UIs.

Use when setting up monorepo tooling, optimizing builds, or migrating between tools with Turborepo, Nx, Bazel, Lerna for efficient task running, caching, and code generation.

Use when Vue 3 Composition API with reactive refs, computed, and composables. Use when building modern Vue 3 applications.

Use when styling React Native components with StyleSheet, Flexbox layout, responsive design, and theming. Covers platform-specific styling and design systems.

Use when React Hooks patterns including useState, useEffect, useContext, useMemo, useCallback, and custom hooks. Use for modern React development.

Use when oTP actor patterns in Gleam including processes, message passing, GenServer implementations, supervisors, fault tolerance, state management, and building concurrent, fault-tolerant applications on the Erlang VM.

Use when next.js Server Components for optimal performance. Use when building data-intensive Next.js applications.

Use when nestJS testing with unit tests, integration tests, and e2e tests. Use when building well-tested NestJS applications.

Use automatically during development workflows when making claims about tests, builds, verification, or code quality requiring concrete evidence to ensure trust through transparency.

Use when Elixir OTP patterns including GenServer, Supervisor, Agent, and Task. Use when building concurrent, fault-tolerant Elixir applications.

Use when Java concurrency with ExecutorService, CompletableFuture, and virtual threads. Use when building concurrent applications.

Guide spec-driven development workflow (Requirements → Design → Tasks → Implementation) with approval gates between phases. Use when user wants structured feature planning or says "use spec-driven" or "follow the spec process".

Use when writing low-level system software in C requiring file I/O, process management, signals, and system calls.

Use when gleam's type system including algebraic data types, custom types, pattern matching, generic types, type inference, opaque types, exhaustive checking, and functional error handling for building type-safe Erlang VM applications.

Use when essential PHP security patterns including input validation, SQL injection prevention, XSS protection, CSRF tokens, password hashing, secure session management, and defense-in-depth strategies for building secure PHP applications.

Use when optimizing Tailwind CSS for production, reducing bundle size, and improving performance. Covers PurgeCSS, JIT mode, and build optimization.

Use when applying Phoenix Framework best practices including context design, controller patterns, and application architecture. Use when building Phoenix applications.