Node-API, RNEF×S3, React Native Harness, AI on iOS, React Universe Conf Countdown

Hey,

It’s Michał delivering the June episode of our newsletter to you! Last month was packed with big news, catching up to WWDC announcements, and experimenting with new APIs. As always, we’ve hand-picked some of the most important updates to the React Native ecosystem, and we’re inviting you to our two biggest conferences: React Universe Conf and React Conf (scroll to the bottom for details).

Community highlights 

• React Native 0.80: Getting closer to a stable JS API, React 19.1, deep imports deprecation, freezing Legacy Architecture, 12% faster builds thanks to prebuilding a few internal iOS libraries (with more to come). Expo users will need to wait for SDK 54 to adopt it.
  
• Unistyles 3.0: React Native Unistyles is now fully rewritten to Nitro Modules and supports only the New Architecture. This release brings a revamped API, Scoped Themes, Compound Variants, Reanimated integration, and smarter style updates with minimal re-renders.
  
• Reddit's iOS App Binary Optimization: The Reddit team shares insights on how they achieved a 20% faster startup thanks to low-level optimization techniques such as LLVM’s Profile-Guided Optimization (PGO), dual profiling (coverage and temporal), partitioning, and Binary Layout Optimization. It’s a fascinating read!
  
• Bluesky app enabled New Architecture: It’s about time to switch. We experienced some blockers when enabling the new architecture for some of our clients, but they were recently resolved in the latest versions of React Native and Reanimated.
  
• Android 16 is here: Available as SDK 36, it comes with a new notifications experience, advanced device protection, and new desktop-style windowing (you can open, move, and resize multiple app windows on a single screen). It’s going to be fun adding that to React Native apps.
  
• Nitro Image: A new Image component powered by Nitro Modules and built in Nitro Views (supporting only new architecture; anybody see a trend here?). Promises fast image loading and, more importantly, image manipulations that are done in-memory. Time to experiment! 

Callstack Incubator highlights  

React Native Node-API 

 We’ve just shipped a thing. In an unprecedented collaboration between Callstack (Mariusz Pasiński), MongoDB (Kræn Hansen), NativeScript (Jamie Birch), Microsoft (Vladimir Morozov), and Rebecker Specialties (Matt Hargett), we’ve released Node-API support for React Native.

It’s a big deal for cross-platform library authors and, hopefully, soon, app developers. Node-API enables unit-testing of native modules in Node.js, cross-platform prebuilds that you can share with Electron, NativeScript, and other frameworks and their versions (thanks to ABI stability), building modules in Rust, Go, Zig, C#, and more.

React Native Enterprise Framework

RNEF now supports AWS S3 and Cloudflare R2 as remote cache providers, which means you can store your app binaries there and keep using our GitHub Actions (use v2 instead of v1, it’s the same API) to handle the building, downloading, and uploading the artifacts for you.

And if you ever tried to add React Native to an iOS app, now is the time to try it again, as we’ve partnered with our React Native Brownfield library to give you the easiest experience yet in just a few steps. Check our latest docs or watch the recording of React Universe Meetup in NYC where I presented that topic with a demo.

We’ve also upgraded the framework to be compatible with React Native 0.80, so you can use the latest toys.

React Native Bottom Tabs

An iOS beta release with a completely new design paradigm (Liquid Glass)? Oskar (and React Native) says: “hold my 🍺”.

It turns out that if you use native primitives, you get native looks for free. Recompile your app for iOS 26 target and enjoy the new looks, as React Native Bottom Tabs supports it from day 2 after the announcement.

React Native AI

Szymon and Mike are hard at work, together recently, to bring the on-device LLM, built into the latest iPhone models through the FoundationModels API, into production with our react-native-ai project. It’s a rough ride, and we file issue after issue on the Apple Developer forum, but it’s getting more stable with every iOS 26 beta.

And since Google announced Gemma 3n models available on the latest Pixel devices, which can operate with as "little" as 2GB and 3GB of memory, we’re onto it as well.

React Native Harness

Szymon is delivering more demos of his latest end-to-end testing library for React Native, which we internally call React Native Harness internally. The project is still in its infancy, but is getting closer to a usable MVP with every week. It’s quite exciting, because it allows for JavaScript-written tests without mocking, especially helpful for React Native library authors, and for regular users who don’t find Detox or Maestro syntax compelling.

In addition to all of that, we released the following content pieces last month:

Blog

• React Native Legal: CLI & Programmatic API - Unified Tooling for License Attributions by Artur Morys-Magiera: Open-source licensing got easier (finally). Meet React Native Legal, a unified tool for automating license attribution (covering both JS and native dependencies) via CLI or API. No more manual copy-pasting, guaranteed.
  
• Caching React Native Builds on S3 and R2 With RNEF by Michał Pierzchała: Say goodbye to unnecessary native builds. RNEF just added remote caching on AWS S3 and Cloudflare R2; ideal for enterprises needing custom CI, compliance, or full control over infrastructure. Less building, more shipping.
  
• How I Used MCP to Control My Friend's Home by Kewin Wereszczyński: Curious about Model Context Protocol? This post shows how MCP helps LLMs like Claude access real-world data. You'll follow a real use case-connecting a smart home API to Claude using a Node server-to see what MCP enables, how it works, and why it is the USB-C of AI tooling.

 Podcast & video

• React Universe On Air Episode #52 Build Faster and Scale Smarter With React Native Enterprise Framework: Discover how React Native Enterprise Framework cuts build times, streamlines CI, and simplifies large-scale app development for growing teams.
  
• React Native Optimization in Practice Episode 3: Stop Shipping Unused Code With R8: Are you shipping unnecessary code in your Android app? You’re probably not alone. In this episode, we show how to use R8, the code shrinker and obfuscator, to reduce the size of your Android builds in React Native.

Live streams

• Live Dev Session: Breaking Down Vercel Ship 2025: Tune in to developer reactions to Vercel Ship 2025, from AI sandboxes and bot detection to smarter compute pricing and microfrontends. Here’s a TL;DR from this session.
  
• Live Dev Session: React Native Styling, OTA, and UI Tools: Watch the recording of a live session unpacking React Native 0.80, OTA alternatives, AI-generated UIs, styling wars, and some truly wild tech tangents. Grab your summary thread here.
  
• Live Dev Session: First Impressions of Apple’s On-Device AI: Tune in to dev chat on Apple’s AI SDK, iOS 26 naming chaos, Siri’s limits, Liquid Glass UI, and on-device LLMs.
  
• Run LLMs Locally With React Native & MLC live stream: Watch how MLC brings on-device AI to React Native. See react-native-ai in action and discover what’s next for local model execution.
• ‍React Universe Meetup, New York live stream: Catch up with the latest React Universe Meetup featuring talks from Mike Grabowski, Pepijn Senders (HelloFresh), David Rifkin (Embrace), and Michał Pierzchała. Talk recordings are coming soon, so stay tuned.

Upcoming events  

React Universe Conf: Two months to go!

• The lineup keeps getting better: Mark Rousavy and TypeScript educator Matt Pocock are joining the speaker roster.
• Heads-up: Regular Access tickets are only available through July. Late Birds go live August 1, so grab your spot while you still can!
• New workshop just dropped: Vercel AI SDK v5: Building AI-powered Apps in TypeScript, led by Matt Pocock himself. Watch the invite and save your spot here.

React Conf 2025

• React Conf is back this October, and the first round of speakers is already live.
• Tickets are lottery-based again this year. Sign up here if you want to attend.

That’s a wrap on June! Catch us online or in person next month, with more tools, more talks, and maybe a surprise or two, because who knows?

Until then, happy shipping!

Michał