How to Migrate to React Native 0.82: Embracing the New Architecture

Introduction

React Native 0.82 marks a pivotal moment—the first version to run entirely on the New Architecture, leaving the Legacy Architecture behind. This guide will walk you through the migration process, ensuring a smooth transition while preparing for future updates. Whether you're still on the old architecture or just updating, these steps will help you leverage the latest improvements, including experimental Hermes V1, React 19.1.1, and DOM Node APIs.

What You Need

• An existing React Native project (version 0.75 or later recommended)
• Node.js (version 18 or later)
• React Native CLI (latest version)
• Xcode (for iOS development) – ensure you have the latest stable version
• Android Studio (for Android development) – with proper SDK setup
• Yarn or npm package manager
• Backup of your project (always a good idea!)

Step-by-Step Migration Guide

Step 1: Upgrade to React Native 0.81 or Expo SDK 54

Before moving to 0.82, you must first upgrade to either React Native 0.81 or Expo SDK 54—the last versions that still support the Legacy Architecture. These releases include helpful warnings and performance improvements tailored for the migration.

1. Run npx react-native upgrade in your project root to apply the version change.
2. If using Expo, run expo upgrade to update to SDK 54.
3. Resolve any dependency conflicts or deprecated API warnings that appear.

Step 2: Enable the New Architecture and Test Thoroughly

In React Native 0.81, you can opt in to the New Architecture to verify your project works correctly before committing to 0.82.

1. Set newArchEnabled=true in your android/gradle.properties file.
2. For iOS, run RCT_NEW_ARCH_ENABLED=1 pod install inside the ios folder.
3. Rebuild and run your app on both platforms.
4. Check for any runtime errors or UI issues. Pay special attention to third-party libraries; if they rely on legacy APIs, you may see warnings.
5. Fix any compatibility issues at this stage—0.82 will no longer allow fallback to the Legacy Architecture.

Step 3: Upgrade to React Native 0.82

Once your app runs smoothly with the New Architecture on 0.81, you’re ready to move to 0.82.

1. Update your package.json to set "react-native": "0.82.0" (or the latest patch).
2. Run npm install or yarn install to fetch the new dependencies.
3. For iOS, run cd ios && pod install to update CocoaPods.
4. For Android, ensure your Gradle files are updated (React Native 0.82 uses the new architecture by default).

Step 4: Verify Compatibility and Remove Legacy Config

In 0.82, settings like newArchEnabled=false are ignored—the New Architecture is enforced. Confirm your project now uses it exclusively.

1. Check that android/gradle.properties does not contain newArchEnabled=false. If present, remove it.
2. Verify that iOS builds succeed without setting RCT_NEW_ARCH_ENABLED=0.
3. Run your app extensively on simulators and real devices to catch any edge cases.

Step 5: Address Third-Party Library Compatibility

Most modern libraries support the New Architecture, but some legacy ones may cause issues.

1. List your third-party dependencies and check their documentation for New Architecture support.
2. If a library is incompatible, contact the maintainer or look for an alternative that works with 0.82.
3. The interop layers are still present in 0.82, so many dual-architecture libraries should function without changes. However, note that these layers will be removed in future versions—plan to migrate any custom native modules soon.

Step 6: Prepare for Future Removal of Legacy Architecture

React Native 0.82 does not delete the Legacy Architecture classes, but the next major version will start removing them to reduce bundle size. Start transitioning now.

1. Review any custom native code (Objective-C, Java, C++) and ensure it uses the New Architecture APIs (e.g., NativeModule with TurboModule conventions).
2. Replace legacy components like RCTViewManager with modern equivalents.
3. Test your app with the experimental Hermes V1 (set hermesVersion: 'v1' in your build config) to catch any JS engine incompatibilities early.

Tips for a Smooth Migration

• Backup first: Always create a backup or use a version control system before starting.
• Test incrementally: Move from 0.81 to 0.82 step-by-step, testing each stage thoroughly.
• Monitor warnings: Pay close attention to deprecation warnings—they’re your roadmap for future changes.
• Use the issue tracker: If you encounter a core bug that blocks migration, report it on the React Native GitHub repository.
• Leverage community resources: Check the React Native blog and release notes for additional tips on Hermes V1 and React 19.1.1 features.
• Plan ahead: With Legacy Architecture classes slated for removal, prioritize converting any custom native modules now to avoid future breakage.

By following these steps, you’ll be well-prepared to adopt React Native 0.82 and the New Architecture, setting your project up for better performance, smaller size, and access to the latest React ecosystem features.