React Native 0.79.x to 0.83.x Migration Assistant

Description

Expert guidance for migrating React Native projects from version 0.79.x to 0.83.x. This skill provides automated detection of breaking changes, step-by-step migration assistance, code fixes, and validation specific to this version upgrade.

When to Use

Use this skill when:

• Upgrading React Native from 0.79.x to 0.83.x (or minor/patch versions within these ranges)

• Encountering build errors after RN upgrade

• Updating Android native modules for RN 0.83.x compatibility

• Migrating MMKV storage code

• Refactoring MainApplication.kt for new architecture

• Validating migration completeness

Triggers

• "migrate react native to 0.83"

• "upgrade from RN 0.79"

• "fix RN 0.83 build errors"

• "update native modules for RN 0.83"

• "MainApplication.kt errors after upgrade"

• "MMKV migration"

Migration Workflow

When invoked, follow this systematic approach:

Phase 1: Pre-Migration Analysis

Detect Current Version

grep "react-native" package.json

Scan for Breaking Change Patterns

• Android native modules using currentActivity

• Android modules with onNewIntent(Intent?)

• MainApplication.kt structure

• MMKV usage (new MMKV() , .delete() )

• Dependency versions

Create Migration Checklist Use TodoWrite to track:

• Dependency updates

• Android native module fixes

• MainApplication.kt refactoring

• MMKV API updates

• Clean build

• Testing

Phase 2: Automated Detection

Run parallel searches to find affected code:

Find native modules with currentActivity

grep -r "currentActivity" android/app/src/main/java

Find onNewIntent with nullable Intent

grep -r "onNewIntent(intent: Intent?)" android/app/src/main/java

Find MMKV usage

grep -r "new MMKV|storage.delete" src/

Find MainApplication

find android/app/src/main/java -name "MainApplication.kt"

Phase 3: Guided Fixes

For each breaking change detected, provide:

3.1 Android Native Module - currentActivity Fix

Detection Pattern:

val activity = currentActivity // or val activity: Activity? = currentActivity

Required Fix:

val activity: Activity? = reactApplicationContext.currentActivity

Action:

• Use Edit tool to replace pattern

• IMPORTANT: Add import android.app.Activity at the top of the file if not present

• Files affected: *Module.kt

• In some modules, you may need to explicitly add the type annotation: val activity: Activity? = ...

3.2 Android Native Module - onNewIntent Fix

Detection Pattern:

override fun onNewIntent(intent: Intent?) {

Required Fix:

override fun onNewIntent(intent: Intent) { // Not needed for this implementation }

Action:

• Use Edit tool to remove ? nullable operator

• Update implementation to handle non-null Intent

• If the method body was empty or had = Unit , replace with a proper implementation or comment

3.3 MainApplication.kt Refactoring

Detection: Check if file contains ReactNativeHost or DefaultReactNativeHost

Required Changes:

• Remove reactNativeHost property

• Update reactHost to use lazy initialization

• Replace SoLoader.init() with loadReactNative(this)

• Update imports

Template:

import com.facebook.react.PackageList import com.facebook.react.ReactApplication import com.facebook.react.ReactHost import com.facebook.react.ReactNativeApplicationEntryPoint.loadReactNative import com.facebook.react.defaults.DefaultReactHost.getDefaultReactHost

class MainApplication : Application(), ReactApplication {

override val reactHost: ReactHost by lazy { getDefaultReactHost( context = applicationContext, packageList = PackageList(this).packages.apply { // Add custom packages add(YourCustomPackage()) // Note: RazorpayPackage() may need to be replaced with RazorpayCustomPackage() // depending on your razorpay-react-native version }, ) }

override fun onCreate() { super.onCreate() loadReactNative(this) // Your custom initialization } }

3.4 MMKV Storage Migration

Detection Patterns:

import { MMKV } from 'react-native-mmkv' new MMKV({ storage.delete(key)

Required Fixes:

import { createMMKV } from 'react-native-mmkv' createMMKV({ storage.remove(key)

Action:

• Use Edit tool for each occurrence

• Typically affects: src/utils/storage.ts

Phase 4: Dependency Updates

Provide exact npm commands:

Core dependencies

npm install react@19.2.0 react-native@0.83.0

Updated dependencies with verified versions

npm install react-native-mmkv@4.1.0 npm install @react-native-async-storage/async-storage@2.2.0 npm install react-native-gesture-handler@2.30.0 npm install react-native-reanimated@4.2.1 npm install react-native-safe-area-context@5.6.2 npm install react-native-svg@15.15.1 npm install react-native-screens@4.19.0 npm install react-native-svg-transformer@1.5.2 npm install react-native-customui@2.2.6 npm install react-native-device-info@15.0.1 npm install react-native-nitro-modules@0.31.10 npm install react-native-nitro-sound@0.2.10 npm install react-native-otp-entry@1.8.5 npm install react-native-worklets@0.7.1

Updated Firebase dependencies (if using)

npm install @react-native-firebase/app@23.7.0 npm install @react-native-firebase/analytics@23.7.0 npm install @react-native-firebase/auth@23.7.0 npm install @react-native-firebase/crashlytics@23.7.0 npm install @react-native-firebase/installations@23.7.0 npm install @react-native-firebase/messaging@23.7.0

Updated navigation dependencies (if using)

npm install @react-navigation/native@7.1.26 npm install @react-navigation/bottom-tabs@7.9.0 npm install @react-navigation/native-stack@7.9.0 npm install @react-navigation/stack@7.6.13

Other updated dependencies

npm install @react-native-google-signin/google-signin@16.0.0 npm install @tanstack/react-query@5.90.12 npm install react-native-video@6.18.0 npm install socket.io-client@4.8.3

Dev dependencies

npm install --save-dev @react-native-community/cli@20.0.0 npm install --save-dev @react-native-community/cli-platform-android@20.0.0 npm install --save-dev @react-native-community/cli-platform-ios@20.0.0 npm install --save-dev @react-native/babel-preset@0.83.0 npm install --save-dev @react-native/metro-config@0.83.0 npm install --save-dev @types/react@19.2.0 npm install --save-dev react-test-renderer@19.2.0 npm install --save-dev jest@29.2.1

Phase 4.1: Node.js Version Check

React Native 0.83.0 requires Node.js >= 20. Verify your Node version:

node --version # Should be v20.x.x or higher

If you need to upgrade Node.js, use nvm or your preferred Node version manager.

Phase 5: Clean Build

Execute build cleanup:

Clean node_modules

rm -rf node_modules package-lock.json npm install

Clean Android

cd android && ./gradlew clean && cd ..

Clean iOS (if applicable)

cd ios && rm -rf Pods Podfile.lock && pod install && cd ..

Reset Metro cache

npx react-native start --reset-cache

Phase 6: Validation

Run validation checks:

Build Validation

Android

npm run android

iOS

npm run ios

Code Pattern Validation

Should return 0 results:

grep -r "currentActivity[^.]" android/app/src/main/java grep -r "Intent?" android/app/src/main/java grep -r "new MMKV" src/ grep -r "storage.delete" src/ grep -r "ReactNativeHost" android/ grep -r "SoLoader.init" android/

Functional Testing Checklist

• App launches without crashes

• Storage read/write works (MMKV)

• Native modules function correctly

• Navigation works

• Third-party integrations work

• No console warnings

Phase 7: Documentation

After successful migration:

• Update CHANGELOG (if exists)

• Document custom changes (if any project-specific modifications were needed)

• Reference main migration guide: docs/solutions/migration-guides/react-native-0.79.x-to-0.83.x.md

Common Issues & Solutions

Issue: "Cannot find symbol: currentActivity"

Quick Fix:

// Replace all occurrences in native modules currentActivity → reactApplicationContext.currentActivity

Issue: "Type mismatch: onNewIntent"

Quick Fix:

// Remove nullable operator override fun onNewIntent(intent: Intent?) { } ↓ override fun onNewIntent(intent: Intent) { }

Issue: "Property 'delete' does not exist on type 'MMKV'"

Quick Fix:

storage.delete(key) → storage.remove(key)

Issue: "Cannot resolve symbol 'ReactNativeHost'"

Quick Fix: Refactor entire MainApplication.kt using the template in Phase 3.3

Files Typically Modified

Track these files during migration:

Android Native Code:

• android/app/src/main/java/*/MainApplication.kt (major refactoring)

• android/app/src/main/java/*/*Module.kt (all custom modules)

JavaScript/TypeScript:

• src/utils/storage.ts (MMKV changes)

• Any file directly using MMKV

Configuration:

• package.json (dependency versions)

• package-lock.json (regenerated)

Rollback Strategy

If migration fails:

Revert all changes

git checkout HEAD -- package.json package-lock.json android/ ios/

Clean install

rm -rf node_modules npm install

Clean build

cd android && ./gradlew clean && cd .. npx react-native start --reset-cache

Success Criteria

Migration is complete when:

✅ All breaking change patterns have been fixed ✅ App builds successfully on Android ✅ App builds successfully on iOS ✅ No runtime crashes on launch ✅ Storage operations work correctly ✅ All native modules function properly ✅ No deprecated API warnings in console ✅ Tests pass

Additional Resources

Reference the comprehensive migration guide:

• Location: docs/solutions/migration-guides/react-native-0.79.x-to-0.83.x.md

• Contains: Detailed explanations, full code examples, testing strategy

External resources:

• React Native Upgrade Helper

• React Native 0.83 Release Notes

• MMKV v4 Migration

Execution Strategy

When user invokes this skill:

• Assess current state - Check if already on 0.83.x or migrating

• Create todo list - Track all migration phases

• Run automated detection - Find all breaking change patterns

• Present findings - Show user what needs to be fixed

• Execute fixes - Apply changes systematically with user approval

• Validate - Run all validation checks

• Document - Update any project-specific documentation

Always use TodoWrite to track progress and keep user informed of migration status.

Version Scope

This skill is optimized for:

• Source versions: React Native 0.79.0 through 0.79.x

• Target versions: React Native 0.83.0 through 0.83.x

• Compatibility: Minor and patch versions within these ranges

For migrations to/from other major versions, refer to official React Native upgrade guides.