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A senior-level guide for building production-ready React Single Page Applications (SPAs) with Vite.

MySQL development best practices for schema design, query optimization, and database administration. \n \n Covers schema design with InnoDB as default engine, appropriate data types (DECIMAL for financial data, utf8mb4 charset), and primary key strategies including AUTO_INCREMENT and UUID storage \n Indexing strategies including B-tree, FULLTEXT, and covering indexes with guidelines on column selectivity and composite index ordering \n Query optimization using EXPLAIN analysis, prepared statemen

Comprehensive guide for building modern React and Next.js applications. Covers performance optimization, component architecture, shadcn/ui patterns, Motion animations, accessibility, and React 19+ features.

End-to-end testing focused on real user behavior, minimal mocking, and avoiding component unit tests. \n \n Prioritizes E2E tests over unit tests; reserves unit tests for pure functions only \n Emphasizes accessible selectors (role-based, label-based) over CSS selectors and test IDs in E2E tests \n Recommends writing E2E tests instead of heavily mocked unit tests; suggests 3+ mocks as a signal to switch approaches \n Includes rules for test structure, selector strategy, and when to apply each te

You are an expert in Sass (the indented syntax), CSS architecture, and maintainable stylesheet development.

Comprehensive Docker best practices for images, containers, and production deployments. \n \n Covers base image selection (Wolfi/Chainguard, Alpine, Distroless), Dockerfile structure with optimal layer ordering, multi-stage builds, and layer optimization techniques to minimize image size and build time \n Includes container runtime security patterns: running as non-root, dropping capabilities, read-only filesystems, resource limits, health checks, and logging configuration \n Provides Docker Com

Architectural patterns for coordinating TanStack Query, Router, and Start across full-stack applications. \n \n Covers setup, data flow, caching, and SSR integration with 13 rules organized by priority and category \n Emphasizes loader-based data fetching with ensureQueryData, suspense queries in components, and server functions as query sources \n Provides unified caching and invalidation strategies to prevent duplication and ensure single source of truth \n Includes automatic SSR dehydration/h

Guidelines for building high-quality Expo React Native applications with JavaScript, focusing on clean code, modularity, and performance.

Simple, pragmatic, opinionated. Only what matters for writing production-grade PostgreSQL queries.

Tamagui v1.x patterns beyond fundamentals: Config v4, compiler optimization, compound components, and gotchas.