Best practices for integrating and using RNRepo — Software Mansion's infrastructure for pre-built React Native library artifacts that reduces native build times by up to 2×. Use when setting up, configuring, or troubleshooting RNRepo in a React Native or Expo project. Trigger on: 'RNRepo', 'rnrepo', 'slow builds', 'build times', 'prebuilt artifacts', 'prebuilt libraries', '@rnrepo/expo-config-plugin', '@rnrepo/build-tools', 'prebuilds-plugin', 'rnrepo.config.json', 'DISABLE_RNREPO', 'packages.rnrepo.org', 'Maven prebuild', 'CocoaPods prebuild', 'xcframework prebuild', 'prebuild AAR', 'build from source', 'native compilation slow', 'Gradle plugin slow', 'pod install slow', 'CI build times'.
React Native JSI (JavaScript Interface) — C++ API for interacting with the JS runtime. Use whenever the user asks about or writes C++ code that touches JSI types or patterns: jsi::Runtime, jsi::Value, jsi::Object, jsi::Function, jsi::Array, jsi::ArrayBuffer, jsi::String, jsi::Symbol, jsi::BigInt, jsi::PropNameID, jsi::HostObject, jsi::HostFunction, jsi::NativeState, jsi::WeakObject, jsi::Scope, JSIException, JSINativeException, JSError, HostFunctionType, createFromHostFunction, getHostObject, setNativeState, evaluateJavaScript, queueMicrotask, drainMicrotasks, setRuntimeData, getRuntimeData, ISerialization, rt.global(), jsi.h, jsi-inl.h, JSI binding, C++ native module, calling JS from C++, calling C++ from JS, HostObject destructor, shared_ptr, CallInvoker, invokeAsync, folly::dynamic with JSI, zero-copy ArrayBuffer, TurboModule C++ layer, Nitro Module, jsi::WithRuntimeDecorator, or any question about the boundary between C++ and the JavaScript engine in React Native.
Software Mansion's best practices for production React Native and Expo apps on the New Architecture. MUST USE before writing, reviewing, or debugging ANY code in a React Native or Expo project. If the working directory contains a package.json with react-native, expo, or expo-router as a dependency, this skill applies. Trigger on: any code task in a React Native/Expo project, 'React Native', 'Expo', 'New Architecture', 'Reanimated', 'Gesture Handler', 'react-native-svg', 'ExecuTorch', 'react-native-audio-api', 'react-native-enriched', 'Worklet', 'Fabric', 'TurboModule', 'WebGPU', 'react-native-wgpu', 'TypeGPU', 'GPU shader', 'WGSL', 'svg', 'animation', 'gesture', 'audio', 'rich text', 'AI model', 'multithreading', 'chart', 'vector', 'image filter', 'shared value', 'useSharedValue', 'runOnJS', 'scheduleOnRN', 'thread', 'worklet', or any question involving UI, graphics, native modules, or React Native threading and animation behavior. Also use when a more specific sub-skill matches.
TypeGPU is type-safe WebGPU in TypeScript. Use whenever the user writes, debugs, or designs TypeGPU code: 'use gpu' shader functions, tgpu.fn, buffers, textures, bind groups, compute and render pipelines, vertex layouts, slots, accessors, and any TypeGPU API. Shader logic and CPU-side resources are tightly coupled - handle both sides here even if the user only mentions one (e.g. "how do I write a shader", "how do I create a buffer"). Trigger on any mention of typegpu, tgpu, "use gpu", TypedGPU, or WebGPU code written using TypeGPU's schema API (d.*, tgpu.*, std.*). Do NOT trigger for raw WebGPU (using GPUDevice/GPURenderPipeline directly without tgpu), WGSL-only questions, Three.js, Babylon.js, or WebGL.
Best practices for building on-device AI features in React Native using React Native ExecuTorch. Use when the user wants to add AI to a mobile app without cloud dependencies: chatbots and assistants, image classification, object detection, OCR and document parsing, style transfer, image generation, speech-to-text, text-to-speech, voice activity detection, semantic search with embeddings, real-time camera AI with VisionCamera, or vision-language image understanding. Also use when the user mentions offline AI, on-device ML, privacy-preserving AI, reducing cloud API costs or latency, running models locally on mobile, or downloading and managing ML models. Covers react-native-executorch hooks (useLLM, useClassification, useObjectDetection, useOCR, useSemanticSegmentation, useInstanceSegmentation, useStyleTransfer, useTextToImage, useImageEmbeddings, useSpeechToText, useTextToSpeech, useVAD, useTextEmbeddings, useExecutorchModule), tool calling, structured output, VLMs, model loading, and resource management.
Software Mansion's guide for migrating Expo SDK apps to Meta Quest using expo-horizon packages. Use when adding Meta Quest or Meta Horizon OS support to an existing Expo or React Native project. Trigger on: Meta Quest, Horizon OS, Quest 2, Quest 3, Quest 3S, VR app, expo-horizon-core, expo-horizon-location, expo-horizon-notifications, build flavors for Quest, panel sizing, VR headtracking, Horizon App ID, quest build variant, isHorizonDevice, isHorizonBuild, migrate expo-location to Quest, migrate expo-notifications to Quest, Meta Horizon Store publishing, or any task involving running an Expo app on Meta Quest hardware.
Production animation patterns for React Native using Reanimated 4, Skia, WebGPU, and TypeGPU. Covers CSS transitions, CSS animations, shared value animations, canvas animations with react-native-skia, GPU shader animations, layout animations, scroll-driven animations, interpolation, particle systems, procedural noise, SDF rendering, performance tuning, and accessibility. Trigger on: Reanimated, useSharedValue, useAnimatedStyle, withSpring, withTiming, withDecay, withRepeat, withSequence, CSS transition, CSS animation, layout animation, FadeIn, SlideIn, ZoomIn, LinearTransition, keyframe, interpolate, scrollTo, useFrameCallback, react-native-skia, Skia Canvas, Atlas, usePathInterpolation, usePathValue, useClock, useTexture, SKSL, interpolateColors, Picture API, canvas animation, sprite animation, WebGPU, react-native-wgpu, TypeGPU, GPU shader, WGSL, particle system, Perlin noise, SDF, Three.js, react-three-fiber, animation performance, or any request to animate UI in React Native.
Software Mansion's best practices for audio in React Native using react-native-audio-api. Covers audio playback (buffer sources, oscillators, streaming), recording (file, callback, graph), audio effects (gain, filters, delay, convolver, panner, waveshaper), real-time analysis and visualization, audio worklets (custom synthesis, UIRuntime/AudioRuntime), system integration (sessions, interruptions, permissions), and testing. Trigger on: react-native-audio-api, AudioContext, AudioRecorder, AudioBuffer, AudioBufferSourceNode, AudioBufferQueueSourceNode, OscillatorNode, StreamerNode, GainNode, BiquadFilterNode, DelayNode, ConvolverNode, StereoPannerNode, WaveShaperNode, AnalyserNode, AudioParam, AudioManager, PlaybackNotificationManager, RecordingNotificationManager, WorkletNode, WorkletSourceNode, WorkletProcessingNode, audio playback, record audio, microphone, waveform, audio visualization, audio streaming, audio worklet, or any React Native feature that captures, processes, or emits sound.