React Native Weekly #43 Expo SDK 58 Beta, Nitro Modules in Core, Direct TypeScript Native Compilation and more

Expo SDK 58 Beta Released#

Expo SDK 58 beta has been released with support for React Native 0.88 RC and iOS 27. It includes expo-app-intents for Siri integration, Expo Modules 2.0 beta, @expo/agent-cli, and more, and can be tested using npx expo install expo@next --fix. https://twitter.com/expo/status/2099972359721795738

Expo Modules 2.0 Adopts Annotation-Based Syntax#

Expo Modules 2.0, currently in development, is switching to an annotation-based approach to specify exposed APIs instead of verbose framework declarations. In addition to reducing boilerplate code, it reportedly improves runtime performance for existing modules. https://twitter.com/tsapeta/status/2100150390473846958

Feedback-Driven Recompilation Added to Hermes Baseline JIT#

A feedback-driven recompilation mechanism has been introduced to the Hermes Baseline JIT. Featuring a simpler design than the speculative optimizing JITs found in V8 or JSC, it boosts performance while keeping runtime overhead low. https://twitter.com/tmikov/status/2099909295295123664

Direct TypeScript Native Compilation Achieves 15ms Startup Time#

The Hermes development team shared experimental results compiling TypeScript directly into native binaries. The binary size is roughly 45MB, achieving a blazing-fast startup time of 15ms. https://twitter.com/tmikov/status/2100064180913225962

Preview of EAS Simulator for AI Agents Released#

Expo has launched a preview of EAS Simulator, which lets AI coding agents verify their changes. It provides an iOS runtime for agents, allowing developers to inspect behavior through session replay videos without having to pull branches locally. https://twitter.com/expo/status/2099491302056616215

Momentum Toward Integrating Nitro Modules into React Native Core#

Following a proposal to integrate Nitro Modules directly into React Native core, author Marc Rousavy expressed his willingness to commit time to the effort. cortinico from the React Native core team also voiced support, and coordination among contributors is moving forward. https://twitter.com/LucasAl23069953/status/2099554678044250189 https://twitter.com/mrousavy/status/2099580666862055705 https://twitter.com/cortinico/status/2099576421848948832

Benchmark Article Published on Embedding Cross-Platform Frameworks into Native Apps#

A Qiita article comparing the performance of embedding KMP, Flutter, and React Native (Expo) as modules into existing native apps was published. It benchmarks initialization overhead and rendering performance when integrating each technology as an add-on. https://twitter.com/mitsuharu_e/status/2099808771191328941

NativeWind v5 Release Candidate Available#

The Release Candidate for NativeWind v5 has been released. If no major issues arise, it is slated to be promoted to the latest stable release in about two weeks. https://twitter.com/nativewindcss/status/2099636691988578593

react-native-gesture-handler 2.33 and 3.3.0 Released#

react-native-gesture-handler 2.33 has been released with support for React Native 0.87 and Android Gradle Plugin 9. This will be the final release in the 2.x line to support React Native 0.87. In parallel, version 3.3.0 has also been published with bug fixes across platforms. https://twitter.com/Michal3870/status/2099417534139117888 https://twitter.com/Michal3870/status/2099483309445370253

Case Study: Enabling DevTools in a New Architecture Production Build#

A case study was shared detailing how React Native DevTools was successfully enabled inside a production build of the Discord app running on the New Architecture. It highlights debugging and inspection techniques for heavily obfuscated and optimized binaries. https://twitter.com/adyarashi/status/2099779876324815047

native-sim: An Open Simulator CLI Introduced#

native-sim, an open simulator environment that eliminates waiting times, has been released. It can be installed with npx i -g native-sim and used for local testing or CI environments. https://twitter.com/bidah/status/2099592187147059416

One More Thing#

The Hermes team’s experiment compiling TypeScript directly into native binaries to hit a 15ms startup time was wild! Even with a hefty 45MB binary size, that kind of startup speed is super exciting!