Breaking: React Native 0.85 Is Now Live with Major Under-the-Hood Changes
Meta and the React Native team have released version 0.85, introducing a new shared animation backend that promises significant performance gains for both the Animated and Reanimated libraries. The release also moves the Jest testing preset to a dedicated package and drops support for end-of-life Node.js versions.
“This update represents a fundamental shift in how animations are processed,” said a React Native core contributor. “By bringing the animation update logic into core, we unlock optimizations that were previously impossible and ensure long-term stability.”
New Shared Animation Backend: A Performance Leap
React Native 0.85 ships the new Shared Animation Backend, developed in collaboration with Software Mansion. This internal engine powers how animations are applied for both the Animated API and the popular Reanimated library.
The backend centralises animation update reconciliation in React Native core, allowing Reanimated to deliver performance improvements that were not feasible before. It also guarantees that the update process is thoroughly tested and remains stable across future React Native releases.
“This is a game-changer for complex animations,” commented a Software Mansion engineer. “Developers can now animate layout properties—like Flexbox and positioning—using the native driver, something previously limited to opacity and transforms.”
To opt in, developers must enable the experimental channel of React Native (starting with version 0.85.1, expected imminently). Example code is available in the rn-tester package under js/examples/AnimationBackend/.
Jest Preset Moved to Dedicated Package
In a breaking change, the Jest preset for React Native has been extracted into its own package. Developers must now install @react-native/jest-preset separately to continue using Jest-based tests.
“This decoupling reduces bloat and allows the preset to evolve independently of React Native releases,” the team explained. Migration instructions are provided in the upgrade guide.
Other Highlights and Breaking Changes
React Native DevTools receive multiple improvements: simultaneous Chrome DevTools Protocol connections (enabling VS Code, DevTools, and AI agents to connect together), native tabs on macOS, and restored request body previews in the Network Panel on Android.
Metro, the JavaScript bundler, now supports TLS configuration for HTTPS and WebSocket Secure (WSS) during development—a long‑requested security enhancement.
Breaking changes include the removal of StyleSheet.absoluteFillObject and the end of support for Node.js versions that have reached their end of life. Developers should review the full changelog for all deprecations.
Background
React Native is Meta’s open-source framework for building cross-platform mobile applications using JavaScript and React. Animation performance has historically been a pain point, with developers relying on either the built-in Animated API or third-party libraries like Reanimated to achieve smooth 60fps interactions.
The Shared Animation Backend addresses architectural limitations that forced animation updates to be processed on the JavaScript thread in certain cases. By moving that logic to the native core, React Native 0.85 bridges a gap that has persisted for years.
What This Means
For developers, the new backend means they can now animate layout properties—such as width, height, margins, and flex values—directly on the native thread. This eliminates performance cliffs when toggling between different layout states.
The separation of the Jest preset signals a trend toward modular tooling, giving testing libraries more agility. However, it also introduces a new dependency that teams must manage.
“This release is a strong signal that React Native is investing deeply in animation infrastructure,” said a senior mobile engineer at a large tech firm. “Combined with DevTools and Metro improvements, it lays the groundwork for more sophisticated development workflows.”
All users are encouraged to upgrade to 0.85, but the animation backend remains experimental until the upcoming 0.85.1 patch. Testing on production apps is recommended only after the stable opt-in is released.