React Native New Architecture: Fabric and TurboModules

The Old Bridge

Async JSON serialization. Slow. Bottleneck for scrolling and animations. The "Bridge" prevented JS from directly calling Native methods.

Replaces the bridge. Allows JS to hold references to C++ Host Objects. JS can call Native methods synchronously. Shared memory!

The new UI system. It moves render logic to C++. It supports React Suspense and Concurrent Mode. No more UI flickering.

Native modules that are lazy-loaded. Instead of initializing all Bluetooth/Camera/Location modules at startup, load them only when requested.

Static type checking between JS and Native. Generates the C++ glue code automatically from TypeScript specs. Prevents type crashes.

JS can now run on different threads. Low priority updates (analytics) don't block high priority updates (animation).

It's a breaking change for native libraries. Library maintainers must rewrite their C++ bindings. Check the "New Arch" compatibility list.