Agent skill · expo
expo-animation
Framework (OSS). Build animations in React Native and Expo, making the decisions in the order that determines whether they feel right — should it animate, which thread it runs on, which properties, spring or timing, how the gesture hands off, how it degrades. Writes the implementation with Reanimated, Gesture Handler, Expo Router and expo-haptics. Use when animating anything in an Expo app, adding gestures, sheets, screen transitions, press feedback or haptics, or fixing motion that stutters on device. For web animation use `animate`.
What it needs
About 12k tokens when loaded.
What this skill does
Building Animations in Expo This skill was created in collaboration with Emil Kowalski and can also be found in the emilkowalski/skills repository, along with other useful animation skills. A construction skill for React Native. It turns a request for motion into an implementation that survives a strict review on a real device — not in the simulator, not on a flagship phone in dev mode. Mobile changes three things about animation, and everything in this skill follows from them: 1. There is no hover. Every affordance the web puts in hover has to live in press, position, or nothing. 2. There are two runtimes. Worklets (Reanimated 4) makes this explicit: the React Native runtime, where React renders and your app logic runs, and the UI runtime, where worklets run every frame (plus optional worker runtimes for background work). An animation that touches the RN runtime stutters the moment the app does anything else. The whole craft is keeping motion on the UI runtime. 3. The user's finger is on the element. Gestures are the primary input, so interruptibility and velocity handoff aren't polish — they're the baseline. Operating Posture You are a senior mobile engineer building the animation yourself. Make the call, state the reasoning in one line, write the code. Never present motion options as a menu. Two failure modes, and the first is worse: 1. Animating something that shouldn't animate. The gate below exists to produce zero lines of code sometimes. 2. Animating the right thing on the wrong thread — a setState per frame, a PanResponder, an animated height. It looks fine in dev on your phone and drops to 20fps on a three-year-old Android. Hard Rules 1. Run the sequence in order. Steps 1 and 2 gate everything. 2. Reanimated, not core Animated. Core Animated can't be driven by a gesture without crossing the bridge, and useNativeDriver refuses anything but transform and opacity anyway. Reanimated worklets run on the UI thread and keep running while JS is busy. 3. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills expo/expo-animation