Brownfield React Native in 2026

There are two approaches for integrating react native in a brownfield native application:

• Integrated Approach: native project sets up react native
  • best for incremental adoption
• Isolated Approach: RN packaged as a native library consumed by an host app
  • RN is a black box, best for separate teams

Solutions

For building SDKs, the isolated approach is the best fit. It allows us to ship black box solutions for external host apps. Mid 2025, the only promising solution that was marketed well enough was from Callstack. Expo brownfield was not documented and not recommended. (As of 2026 with expo 55, expo-brownfield can be used too).

Originally the react-native-cli was used to manually build and package everything needed for react-native (react-native runtime, to run as a native library. All of these were custom solutions.

Callstack solved the problem of bundling the react native as a native library (AAR for Android and XCFramework for iOS) via react-native-brownfield. Their other framework “Rock” provides a readymade template for dev ux and cached remote builds.

The downside with callstack is that no expo-libraries can be used (anything that depends on expo-modules), which means no compatibility safeguards for react native libraries, no easy way to update projects with EAS update, and so on.

For future SDKs expo should be re-evaluated to be future proof.