Build beautiful native iOS/Android apps with Expo Router. Covers route structure, native tabs, animations, blur effects, liquid glass, SF Symbols, and platform patterns.

WHAT: Production-ready Node.js backend patterns - Express/Fastify setup, layered architecture, middleware, error handling, validation, database integration, authentication, and caching. WHEN: User is building REST APIs, setting up Node.js servers, implementing authentication, integrating databases, adding validation/caching, or structuring backend applications. KEYWORDS: nodejs, node, express, fastify, typescript, api, rest, middleware, authentication, jwt, validation, zod, postgres, mongodb, redis, caching, rate limiting, error handling

SLURM and HPC guidance for Mycelia benchmarks and large-scale analysis

Name | Type | Description | Notes

Create software diagrams using Mermaid syntax. Use when users need to create, visualize, or document software through diagrams including class diagrams, sequence diagrams, flowcharts, ERDs, C4 architecture diagrams, state diagrams, git graphs, and other diagram types. Triggers include requests to diagram, visualize, model, map out, or show the flow of a system.

Update an existing skill with improvements

GPU VRAM management patterns for sharing memory across services (Ollama, Whisper, ComfyUI). OOM retry logic, auto-unload on idle, and service signaling protocol.

API versioning strategies — URL path, header, query param, content negotiation — with breaking change classification, deprecation timelines, migration patterns, and multi-version support. Use when evolving APIs, planning breaking changes, or managing version lifecycles.

Error handling patterns across languages and layers — operational vs programmer errors, retry strategies, circuit breakers, error boundaries, HTTP responses, graceful degradation, and structured logging. Use when designing error strategies, building resilient APIs, or reviewing error management.

This skill empowers Claude to build reusable Terraform modules based on user specifications. It leverages the terraform-module-builder plugin to generate production-ready, well-documented Terraform module code, incorporating best practices for security, scalability, and multi-platform support. Use this skill when the user requests to create a new Terraform module, generate Terraform configuration, or needs help structuring infrastructure as code using Terraform. The trigger terms include "create Terraform module," "generate Terraform configuration," "Terraform module code," and "infrastructure as code."

Write specification documents for features using specification-driven development practices, including requirements with user stories, architecture design documents with correctness properties, and implementation plans with task breakdowns. Use when planning a new feature, designing system architecture, creating implementation roadmaps, or documenting technical specifications.

Patterns for skeleton loaders, shimmer effects, and loading states that match design system aesthetics. Covers skeleton components, shimmer animations, and progressive loading. Use when building polished loading experiences. Triggers on skeleton, loading state, shimmer, placeholder, loading animation.

React and Next.js performance optimization guidelines from Vercel Engineering. 57 rules across 8 categories for writing, reviewing, and refactoring React code.

Plan content aligned with user personas and journey stages. Use when asked to "plan content," "create content strategy," "build editorial calendar," "map content to personas," "audit existing content," or when aligning marketing/docs content with user journeys defined in persona docs.

Google Gemini API integration for building AI-powered applications. Use when working with Google's Gemini API, Python SDK (google-genai), TypeScript SDK (@google/genai), multimodal inputs (image, video, audio, PDF), thinking/reasoning features, streaming responses, structured outputs with JSON schemas, multi-turn chat, system instructions, image generation (Nano Banana), video generation (Veo), music generation (Lyria), embeddings, document/PDF processing, or any Gemini API integration task. Triggers on mentions of Gemini, Gemini 3, Gemini 2.5, Google AI, Nano Banana, Veo, Lyria, google-genai, or @google/genai SDK usage.

Opinionated guide for building dApps on Arbitrum using Stylus (Rust) and/or Solidity. Covers local devnode setup, contract development, testing, deployment, and React frontend integration with viem. Use when starting a new Arbitrum project, writing Stylus or Solidity contracts, deploying to Arbitrum, or building a frontend that interacts with Arbitrum contracts.

Create distinctive, production-grade frontend interfaces that avoid generic "AI slop" aesthetics. Focuses on creative direction and memorable design choices.

Dual-stream event publishing combining Kafka for durability with Redis Pub/Sub for real-time delivery. Use when building event-driven systems needing both guaranteed delivery and low-latency updates. Triggers on dual stream, event publishing, Kafka Redis, real-time events, pub/sub, streaming architecture.

[Alexa](https://developer.amazon.com/alexa) is Amazon's cloud-based voice service. Most people are familiar with the service through using an [Amazon Echo or Echo dot](https://developer.amazon.com/alexa/echo) but the service can also be integrated in to custom internet-connected devices like this talking robotic fish:

Comprehensive UI design skill covering fundamentals, patterns, and anti-patterns. Layout, typography, color, spacing, accessibility, motion, and component design. Use when building any web interface, reviewing design quality, or creating distinctive UIs.