React Native Core

Shared model for the react-native cluster. UI and interaction spokes depend on these runtime facts — keep them consistent. For build/ship/Expo specifics, see expo-core.

1. Architecture (know which you're on)

• New Architecture (default on recent RN): Fabric renderer, TurboModules (lazy native modules), JSI (direct JS↔native, no async bridge), bridgeless mode. Enables synchronous calls and better perf.
• Old bridge (legacy): async, serialized JSON bridge — the bottleneck the New Arch removes.
• Most decisions (Reanimated worklets, synchronous measurements) assume the New Architecture.

2. Styling

• StyleSheet + Flexbox is the baseline (Flexbox defaults differ from web: flexDirection: 'column', no px).
• NativeWind / Tailwind for utility styling across native + web → expo-tailwind-setup.
• Platform-specific styles via Platform.select or .ios.tsx / .android.tsx files.

3. Navigation