callstackincubator Migrating to React Native
Overview
Prescriptive workflow for incremental adoption of React Native in existing native apps using @callstack/react-native-brownfield, from initial setup through phased host integration.
- Expo track
- Bare React Native track
Use one track per task unless the user explicitly asks for migration or comparison.
Migration Strategy
Use this strategy for brownfield migration planning and execution:
- Assess app state and select Expo or bare path.
- Perform initial setup with
@callstack/react-native-brownfield. - Package RN artifacts (
XCFramework/AAR) from the RN source app. - Integrate one RN surface into the host app and validate startup/runtime.
- Repeat integration by feature/screen for incremental rollout.
Agent Guardrails (Global)
Apply these rules across all reference files:
- Select one path first (Expo or bare) and do not mix steps.
- Use placeholders from the docs (
<framework_target_name>,<android_module_name>,<registered_module_name>) and resolve from project files. - Validate each packaging command before moving to host integration.
- Prefer official docs for long platform snippets and CLI option details.
- Keep host apps isolated from direct React Native APIs when possible (facade approach).
Canonical Docs
- Quick Start
- Expo Integration
- iOS Integration
- Android Integration
- Brownfield CLI
- Guidelines
- Troubleshooting
Path Selection Gate (Must Run First)
Before selecting any reference file, classify the project:
- If no React Native app exists yet, use Expo creation path:
- expo-create-app.md -> expo-quick-start.md
- If React Native app exists, inspect
package.jsonandapp.json:- Expo if
expois present or Expo plugin workflow is requested. - Bare RN if native folders and direct RN CLI workflow are used without Expo path requirements.
- Expo if
- If still unclear, ask one disambiguation question.
- Continue with exactly one path.
When to Apply
Reference this package when:
- Planning incremental migration from native-only apps to React Native or Expo
- Creating brownfield integration flows for Expo or bare React Native projects
- Performing initial setup with
@callstack/react-native-brownfield - Generating iOS XCFramework artifacts from a React Native app
- Generating and publishing Android AAR artifacts from a React Native app
- Integrating generated artifacts into host iOS/Android apps
Quick Reference
| File | Description |
|---|---|
| quick-start.md | Shared preflight and mandatory path-selection gate |
| expo-create-app.md | Scaffold a new Expo app before Expo brownfield setup |
| expo-quick-start.md | Expo plugin setup and packaging readiness |
| expo-ios-integration.md | Expo iOS packaging and host startup integration |
| expo-android-integration.md | Expo Android packaging, publish, and host integration |
| bare-quick-start.md | Bare React Native baseline setup |
| bare-ios-xcframework-generation.md | Bare iOS XCFramework generation |
| bare-android-aar-generation.md | Bare Android AAR generation and publish |
| bare-ios-native-integration.md | Bare iOS host integration |
| bare-android-native-integration.md | Bare Android host integration |
Problem -> Skill Mapping
| Problem | Start With |
|---|---|
| Need path decision first | quick-start.md |
| Need to create a new Expo app for brownfield | expo-create-app.md |
| Need Expo brownfield setup and plugin wiring | expo-quick-start.md |
| Need Expo iOS brownfield integration | expo-ios-integration.md |
| Need Expo Android brownfield integration | expo-android-integration.md |
| Need bare RN baseline setup | bare-quick-start.md |
| Need bare RN iOS XCFramework generation | bare-ios-xcframework-generation.md |
| Need bare RN Android AAR generation/publish | bare-android-aar-generation.md |
| Need bare RN iOS host integration | bare-ios-native-integration.md |
| Need bare RN Android host integration | bare-android-native-integration.md |