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45 performance optimization rules for React and Next.js, organized by impact from critical waterfalls and bundle size down to advanced patterns. \n \n Covers 8 rule categories prioritized by performance impact: eliminating waterfalls, bundle optimization, server-side performance, client-side data fetching, re-render optimization, rendering performance, JavaScript performance, and advanced patterns \n Each rule includes explanations, incorrect/correct code examples, and context to guide automated

Styling guidelines for the Mastra Playground UI, containing 5 rules across 3 categories. Rules are prioritized by impact to guide automated refactoring and code generation. These rules ensure design system consistency, prevent token drift, and maintain component library integrity.

Laravel Eloquent query optimization and relationship management patterns with N+1 prevention. \n \n Eager load relationships with with() and use withCount() for efficient aggregations instead of triggering additional queries in loops \n Select only needed columns at query time and define return types on relationship methods for better IDE support and clarity \n Use query scopes to encapsulate reusable filtering logic and leverage database-level operations ( update() , increment() ) instead of lo

Comprehensive performance optimization guide for React and Next.js applications, maintained by Vercel. Contains 45 rules across 8 categories, prioritized by impact to guide automated refactoring and code generation.

51 rules for writing clean, type-safe, modern PHP 8.x code aligned with PSR standards and SOLID principles. \n \n Covers 7 rule categories: type system, modern PHP features (8.0–8.5), PSR standards, SOLID principles, error handling, performance, and security \n Version-aware guidance that detects PHP version from composer.json and runtime, recommending only features available in the target version \n Organized by priority: type safety and security are critical; modern features and SOLID principl

Structured guidance for designing, executing, and analyzing content experiments to improve conversion and engagement. \n \n Covers hypothesis frameworks, metric selection, sample size calculation, and statistical significance testing across A/B and multivariate experiments \n Includes detailed resources on p-values, confidence intervals, power analysis, and Bayesian methods for interpreting results \n Provides CMS integration patterns for managing variants at the field level and connecting exter

Comprehensive guidance for building modern ecommerce storefronts with patterns, component architecture, and backend integration. \n \n Covers all storefront components: navigation, product pages, cart, checkout, and account pages across any framework (Next.js, SvelteKit, React, Vue) \n Includes critical accessibility patterns (aria-live for cart updates), mobile optimization (safe-area-inset, 44px touch targets), and SEO requirements (Product schema, Core Web Vitals) \n Provides mandatory backen

Language and framework-specific security reviews with actionable vulnerability detection and fix guidance. \n \n Supports Python, JavaScript/TypeScript, and Go with framework-specific best practices loaded from a references directory \n Operates in three modes: secure-by-default code generation, passive vulnerability detection during development, and full security audit reports with severity prioritization \n Generates detailed markdown reports with line-number references, impact statements, and

Comprehensive guidance for building Fastify Node.js backends with TypeScript, covering routes, plugins, validation, and production deployment. \n \n Covers 16+ core topics including plugins, route organization, JSON Schema validation, error handling, hooks, authentication, testing, logging with Pino, and TypeScript integration via strip types \n Includes recommended reading paths for common scenarios: new projects, adding authentication, performance optimization, testing setup, and production de

Comprehensive Vue.js testing guidance covering unit, component, and end-to-end testing strategies. \n \n Addresses 11 common testing challenges including async handling, composable testing, Pinia store setup, Suspense components, and Teleport queries \n Recommends Vitest for unit and component testing infrastructure, with Playwright as the preferred E2E framework \n Covers black-box component testing patterns to reduce brittleness during refactoring, async/await synchronization, and snapshot tes