React Native 0.85 Rolls Out Groundbreaking Animation Backend, Restructures Jest Setup

Breaking: React Native 0.85 Released with Major Performance Overhaul

The React Native team today announced the release of version 0.85, introducing a new shared animation backend built in partnership with Software Mansion. This update redefines how animations are processed under the hood, promising significant performance gains for both the Animated and Reanimated libraries.

"Moving the core animation update logic into React Native itself allows Reanimated to achieve optimizations previously impossible, and ensures long-term stability across future releases," said a React Native core contributor. The new backend also enables animating layout props with the native driver in Animated—a feature that was restricted until now.

Developers can opt in to the experimental backend starting from React Native 0.85.1, which is expected imminently. Full documentation and examples are available in the rn-tester package.

DevTools and Metro Enhancements

React Native DevTools gains support for multiple simultaneous Chrome DevTools Protocol connections, enabling tools like VS Code and AI agents to attach concurrently without session conflicts. A macOS update now includes native tab handling via Window > Merge All Windows.

On Android, request body previews in the Network panel have been restored after a regression. Meanwhile, Metro’s dev server can now accept a TLS configuration, enabling HTTPS and secure WebSocket connections for Fast Refresh during development.

Breaking Changes: Jest Preset, Node.js Support, StyleSheet Removal

Several breaking changes accompany this release. The Jest preset has been moved to a dedicated package (@react-native/jest-preset), requiring developers to update imports. Support for end-of-life Node.js versions has been dropped, and StyleSheet.absoluteFillObject has been removed entirely.

"These changes streamline the React Native ecosystem and reduce technical debt," the team noted. Users are advised to review the full migration guide on the official repository.

Background: A Long-Awaited Animation Overhaul

React Native’s animation system has long been a pain point for performance‑sensitive apps. Prior to 0.85, layout property animations required the JavaScript thread, causing jank on complex interfaces. The new backend, co‑created with Software Mansion—known for react-native-reanimated—addresses this by natively driving updates for both basic and advanced animation libraries.

Version 0.85 also continues a trend of modularizing core tooling. The Jest preset extraction follows previous moves to separate packages for testing utilities, reflecting an ongoing effort to reduce the core bundle size and improve maintainability.

What This Means for Developers

With the new animation backend, developers can now animate Flexbox and positioning properties like width, height, and top using the native driver—removing a major bottleneck for smooth UI transitions. Early benchmarks indicate up to 60 fps animations even on mid‑range devices, a leap from the 30‑fps ceiling common with JavaScript‑driven layouts.

The DevTools improvements translate into more productive debugging. Multi‑connection support means that developers can run React Native DevTools alongside VS Code extensions or automated testing agents without unexpected disconnections. Secure Metro connections also simplify developing with remote servers or internal networks.

However, teams must update their Jest configuration and ensure they run Node.js 18+. The removal of StyleSheet.absoluteFillObject encourages migration to StyleSheet.absoluteFill for cleaner code. Overall, React Native 0.85 positions the framework as more robust for high‑performance mobile apps, while shedding legacy baggage.

React Native 0.85 is available now via npm. Developers should review the breaking changes above before upgrading.