Fabric and TurboModules New Architecture opt-in leaves legacy bridge deprecation timeline unresolved

Direct answer

In recent stable React Native releases, Fabric and TurboModules are opt-in rather than default. The legacy Paper renderer and JavaScript bridge remain the default code path unless newArchEnabled is explicitly set to true. Hermes is the default JavaScript engine, but that is a separate decision and does not imply the New Architecture is enabled. No official removal date or deprecation schedule has been published for Paper or the legacy bridge.

Confirmed facts versus likely explanation

Confirmed: React Native maintains both the legacy bridge and New Architecture code paths. Enabling Fabric and TurboModules requires explicit opt-in through newArchEnabled in Android Gradle configuration and the CocoaPods install configuration on iOS. Library code generated with React Native codegen can target TurboModules, while legacy modules continue to load through the bridge.

Likely explanation: Because the New Architecture remains opt-in, the project has not committed to a published sunset date for the legacy bridge. The unresolved timeline reflects ongoing backward-compatibility maintenance for existing apps and libraries, not an announced transition plan.

Verification steps

1. Open android/gradle.properties and confirm whether newArchEnabled=true is present.
2. Open ios/Podfile and check the install! 'cocoapods' options for a New Architecture flag.
3. Run npx react-native --version and compare the result against the release notes for that stable version.
4. Search the installed React Native package or repository release notes for deprecation or removal language targeting Paper or the legacy bridge.

Library author decision

Maintain dual bridge compatibility when your minimum supported React Native version includes apps still running the legacy bridge, or when you cannot verify that all consumers have migrated. Ship a TurboModule spec generated by codegen alongside the legacy bridge module, gate native implementation by architecture flag, and test both newArchEnabled states.

Choose TurboModules-only when your library requires New Architecture features, your minimum React Native version assumes the New Architecture, or maintaining two native implementations is impractical. This excludes legacy-bridge apps, so document the requirement clearly.

Assumptions and uncertainty

• This answer assumes a recent stable React Native release where newArchEnabled is the opt-in mechanism. Defaults can change in future stable releases.
• The absence of a published schedule is not a guarantee of permanent legacy support. Treat the legacy bridge as temporary and monitor official React Native announcements.
• No specific removal date or version was verified against live documentation; this draft requires human review before publication.

Missing diagnostic detail that could change the recommendation: your project’s current React Native version and whether newArchEnabled is already enabled. If it is enabled, TurboModules-only support may be viable sooner; if not, dual compatibility remains the safer default.