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Build Next.js 16 apps with async route params, Server Components, Cache Components, and Partial Prerendering. \n \n Covers 25+ documented errors and solutions, including async params migration, parallel routes with required default.js , and \"use cache\" directive patterns \n Supports Cache Components with revalidateTag() , updateTag() , and refresh() APIs for opt-in caching and stale-while-revalidate strategies \n Includes proxy.ts migration (replaces deprecated middleware.ts), Turbopack produc

Automate App Store Connect app creation by driving the web UI form with browser automation. \n \n Requires a pre-registered bundle ID in the Apple Developer portal and user sign-in to App Store Connect; handles multi-platform selection (iOS, macOS, tvOS, visionOS) and all required fields including the tricky User Access radio buttons \n Includes detailed workarounds for known UI quirks: dropdown menu navigation for \"New App\", asynchronous Bundle ID dropdown loading, and span-overlay intercepti

Use XcodeBuildMCP tools via the xcodebuildmcp executable instead of raw xcodebuild, xcrun, or simctl.

Comprehensive guide for building high-quality MCP servers that enable LLMs to interact with external services. \n \n Four-phase workflow covering research, implementation, review, and evaluation with detailed checklists and best practices for each stage \n Agent-centric design principles including workflow optimization, context efficiency, actionable error messages, and evaluation-driven development \n Language-specific implementation guides for Python (FastMCP) and Node/TypeScript with SDK docu

Sentry error monitoring, session replay, and tracing for React applications. \n \n Install @sentry/react and initialize via instrument.js (imported first in your entry point) with DSN configuration \n Supports error capture via React 19+ error hooks or ErrorBoundary component for earlier versions \n Includes browser tracing, session replay, and Redux integration; router integrations available for React Router (v4–v7) and TanStack Router \n Source map upload via @sentry/wizard enables readable st

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

Rust naming, formatting, and best-practice guidelines covering 50 core rules. \n \n Covers naming conventions (no get_ prefix, iterator patterns, conversion methods), data types (newtypes, slice patterns, pre-allocation), and string handling (prefer bytes for ASCII, use Cow<str> when appropriate) \n Error handling guidance includes ? propagation over try!() , meaningful lifetime names, and lock ordering for concurrency safety \n Includes deprecation mappings (e.g., lazy_static! to OnceLock

Create original visual designs by developing aesthetic philosophies, then expressing them through meticulously crafted .png or .pdf artwork. \n \n Two-step process: first generate a design philosophy manifesto (4–6 paragraphs articulating visual principles around form, space, color, and composition), then express it as a single-page or multi-page visual artifact \n Emphasizes sparse, essential-only text integrated as visual element; ideas communicate through spatial relationships, color zones, t

A five-day process for answering critical business questions through design, prototyping, and testing ideas with customers. Developed at Google Ventures and used by Google, Slack, Airbnb, and hundreds of startups.

45 performance optimization rules for React and Next.js, organized by impact and category. \n \n Covers 8 rule categories from eliminating waterfalls and bundle optimization (critical) through JavaScript performance and advanced patterns (low priority) \n Each rule includes explanation, before/after code examples, and context to guide automated refactoring and code generation \n Prioritized by impact: waterfalls and bundle size are critical; server-side performance and re-render optimization are