patterns▌

Architectural patterns, API design, and database optimization for Node.js, Express, and Next.js backends. \n \n Covers repository, service, and middleware layers for clean separation of concerns; includes REST API structure with resource-based URLs and query parameters \n Database patterns include N+1 prevention, query optimization, transactions, and caching strategies (Redis, cache-aside) \n Error handling with centralized handlers, retry logic with exponential backoff, and structured logging f

Production-ready Tailwind CSS patterns for responsive layouts, cards, forms, buttons, and navigation. \n \n Includes semantic color tokens for automatic light/dark mode support, eliminating raw color usage that breaks themes \n Covers mobile-first responsive design with six breakpoints (base, sm, md, lg, xl, 2xl) and consistent spacing scale (4, 6, 8, 12, 16, 24) \n Provides ready-to-use component patterns for headers, footers, grids, cards, buttons, forms, and typography with hover states and t

Production-grade Bash scripting with strict error handling, defensive patterns, and safety best practices. \n \n Covers 10 fundamental patterns including strict mode ( set -Eeuo pipefail ), error trapping, variable quoting, array handling, and safe temporary file management \n Includes advanced techniques for argument parsing, structured logging, process orchestration with signals, and idempotent script design \n Provides templates for function definitions, file operations, command substitution,

Modern React 19 patterns for Server Components, Actions, concurrent features, and TypeScript development. \n \n Covers core hooks (useState, useEffect, useRef, useMemo, useCallback) with TypeScript typing and custom hook extraction patterns \n Includes React 19 features: use() hook, useOptimistic, useFormStatus, useFormState, Server Actions, and Server Components with mixed architecture examples \n React Compiler automatic optimization eliminates manual memoization; includes setup, configuration

Fundamental design principles for writing maintainable, testable Python code. \n \n Covers five core patterns: KISS (Keep It Simple), Single Responsibility Principle, Separation of Concerns, Composition Over Inheritance, and the Rule of Three \n Includes practical code examples contrasting anti-patterns with recommended approaches for each principle \n Provides layered architecture guidance (API, Service, Repository layers) with dependency injection patterns for testability \n Emphasizes explici

Efficient similarity search patterns for vector databases and semantic retrieval systems. \n \n Covers four major vector database implementations: Pinecone, Qdrant, pgvector with PostgreSQL, and Weaviate, each with production-ready code templates \n Explains three index types (Flat, HNSW, IVF+PQ) with trade-offs between search speed, recall accuracy, and data scale \n Includes four distance metrics (Cosine, Euclidean, Dot Product, Manhattan) and guidance on when to use each \n Demonstrates hybri

Design durable distributed workflows with Temporal, separating orchestration logic from external interactions. \n \n Workflows handle orchestration and decision-making (must be deterministic); activities handle external calls like APIs and databases (must be idempotent) \n Implements saga pattern with compensation for distributed transactions, entity workflows for long-lived state management, and fan-out/fan-in for parallel execution \n Automatic state preservation across failures via event hist

Advanced Next.js patterns for authentication, middleware, Server Actions, and user-scoped caching with Clerk. \n \n Distinguishes server-side await auth() from client-side useAuth() hook; mixing them is a common breaking mistake \n Covers middleware strategies (public-first vs protected-first), API route protection, and proper HTTP status codes (401 vs 403) \n Includes user-scoped caching patterns with unstable_cache and protecting Server Actions from unauthorized mutations \n Provides Core 2 co

Comprehensive guide to building reliable, maintainable end-to-end test suites with Playwright and Cypress. \n \n Covers both Playwright and Cypress with setup, configuration, and framework-specific patterns including Page Object Model, fixtures, network mocking, and custom commands \n Addresses core E2E testing philosophy, the testing pyramid, and best practices for deterministic, independent tests using data attributes and user-behavior assertions \n Includes advanced patterns for visual regres

Design patterns for building autonomous coding agents, inspired by Cline and OpenAI Codex.