A new animation backend in React Native core

React Native 0.85 introduces a shared animation backend built together with Software Mansion. The key shift is moving animation update logic into React Native core, creating a unified mechanism for applying style updates across different animation libraries.

Previously, libraries like Reanimated and others operated independently, often competing to update the shadow tree. The new backend separates animation updates into a dedicated pipeline, reducing conflicts and making rendering behavior more predictable. It also sets a more stable foundation for future React Native changes.

Better support for layout animations

This release improves how layout-related properties can be animated. In earlier versions, animating properties like top, left, or margin came with tradeoffs, often tied to JavaScript thread execution and layout recalculations.

With the new backend, more animation work can run off the JavaScript thread. This opens the door to smoother layout animations without relying on transform-based workarounds, and reduces the performance penalties developers previously had to consider.

DevTools and Metro improvements

React Native DevTools now support multiple simultaneous connections using the Chrome DevTools Protocol, making debugging more flexible across different tools. There are also improvements to request inspection, including clearer payload previews.

Metro adds support for TLS configuration, enabling HTTPS and secure WebSocket connections during development. This is especially useful when working with APIs that require secure communication even in local environments.