Voltra Launch, React Navigation 8 Alpha, Brownfield “Brownie”, and React Native AI x llama.rn

Hey,

It’s Michał with the first update of 2026!

I hope your new year’s resolution are holding up (hint: focus on making habits and enjoying the process, not just goals) and you’re well rested to build new things. And if you’re not ready to ship just yet, here’s a bunch of news and insights from React Native community and Callstack Incubator in December 2025 and early January to prime you with inspiration instead of FOMO. Let’s go!

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Community highlights

• Hermes now has a blog: Tzvetan from Hermes team went on a journey of converting his famous X posts about Hermes JS engine internals to a structured blog in the projects’ GitHub repo. We highly recommend reading all of it!
• Debug Like a Senior - React Native Performance Panel: Mariusz shares how to efficiently use new Performance Panel in React Native DevTools. He goes through the panel's features, such as Scheduler tracks, Components, Threads, and also reveals some hidden gems. Can you find them?
• MLX Swift with React Native: MLX is a NumPy-like array framework designed for efficient and flexible machine learning on Apple silicon, brought to you by Apple machine learning research. There’s now a React Native library wrapping Swift MLX using Nitro Modules.
• RNSec: React Native Security Scanner: a new project that allows you to detect vulnerabilities, hardcoded secrets, and security misconfigurations before they reach production. It’s a CLI that also creates a rich HTML report. Supported rules verify issues around storage, network, WebView, logging, config, third-party SDKs and more.
• React Native Wrapped 2025: A Month-by-Month Recap of The Year: together with Szymon Rybaczk we’re looking back at the year React Native turned 10 and the ecosystem doubled down on the New Architecture. The article provides a month-by-month record of 2025, covering major framework releases, the Legacy Architecture freeze, React 19 integration, and notable developments across tooling, performance, styling, native modules, Expo, and platform adoption.

Callstack Incubator highlights  

Voltra

Long-teased by Szymon, it’s finally out! Voltra is a React renderer for iOS Live Activities, Dynamic Island and Widgets. With Voltra you can build dynamic live activities running locally, or driven from a server with push notifications, using only TypeScript. No Swift knowledge required. The library is a joint collaboration between Szymon and its original author Saúl.

React Native Brownfield

Oskar is working on a new addition to our Brownfield library: a two-way, end-to-end type-safe, cookie-like storage for communicating between Native and React Native called Brownie. It’s gonna be pretty sweet addition to your hybrid apps, or incremental migration, so that you can be sure that there’s a single source of truth for the state shared by native and React Native components. Watch out for release in the upcoming weeks!

And if you haven’t heard about it already, you can also pair the React Native Brownfield library with Expo too! You’ll need to prebuild the app, so no CNG yet, but we may be working on something in this area 🤫.

React Native Pager View

Another great contribution by Oskar, driven by the needs of Vercel’s v0 mobile app. This one is about rewriting the slightly buggy UIKit implementation to SwiftUI, which solves some of the long standing issues we’ve found in many high-profile apps out there using the library. Upgrade PagerView to v8 and let us know how it works for you and your users.

React Native Bottom Tabs

The React Native Bottom Tabs library by Oskar was successfully incubated and is now part of Callstack organization. This means we treat it as stable, feature ready, and we keep maintaining it. Well done Oskar! 🎉

Rozenite

Szymon is building yet another DevTools plugin using Rozenite, this time it’s about profiling import cost for Metro bundles. You, or Claude Code, can build your own plugins using Rozenite too. 😁

React Native AI x llama

Wake up, there’s new runtime compatible with React Native AI: llama.rn.

It allows you to use the same AI SDK interface with llama.cpp project (through llama.rn) to run GGUF models. Such as the newly released Gemma 3 270M.

We’re also working on ONNX support, so expect that next month or so.

React Navigation

Satya is fearlessly closing issues, PRs, and delivering new features for the upcoming React Navigation 8 release. And now you can have a sneak peek of what’s coming with the latest alpha release! It features native bottom tabs, accessing route, navigation, and state for any parent screens, better inferred types, and more. Check the blog post too.

SceneDelegate RFC

Artur converted his draft PR into a formal RFC for SceneDelegate migration for iOS. Since iOS 26 started deprecating AppDelegates, it’s becoming inevitable that we’ll need to migrate to UIScene lifecycle. Read the proposal and leave some comments or reactions. We hope to ship this in the upcoming months.

Storybook explorations

Since Danny joined Callstack recently, he’s been hacking on a few things in his spare time outside of Incubator, but closely with its members, such as Szymon. Together they prototyped a small app that streams simulator screens to a unified web UI, so that you can work on your React components in Storybook and see how they work at all platforms all at once. Should we followup with a more robust library for that? Let us know!

Create React Native Library (Bob)

There’s a new version of CRNL which supports latest Rect Native, reworked its CLI, fixed Nitro View template and some issues on Windows. Hopefully next version will include Harness by default, so you’ll be able to test your libraries end-to-end with Jest.

Guide

React Native Developer’s Guide to Horizon OS

As a culmination of the Meta Quest–focused content we’ve been publishing recently, we’re releasing a brand-new guide! The React Native Developer’s Guide to Horizon OS shows how React Native apps can run on Meta Quest headsets without switching stacks. Because Meta Horizon OS is built on Android, React Native works where you’d expect: same core abstractions, familiar tooling, and a new spatial form factor.

The guide is written for React Native developers who already ship on mobile or web and want a practical, no-hype path into VR.

It covers:

• How React Native fits into Meta Horizon OS and what actually changes in VR
• Setting up and running React Native apps on Meta Quest with Expo
• Library compatibility, ecosystem constraints, and Quest-ready alternatives
• App categories that make sense in VR and how to think spatially
• Debugging, performance profiling, native modules, and daily workflows
• Building, signing, and publishing a production-ready app to the Meta Horizon Store

The result is a clear, hands-on guide to building and shipping real React Native apps on Meta Quest, using the skills and workflows you already have.

Blog

If you prefer to jump straight to the blog post versions of our releases, there you go:

• Live Activities and Widgets with React: Say Hello to Voltra by Szymon Chmal & Saúl Sharma
• React Native Wrapped 2025: A Month-by-Month Recap of The Year by Michał Pierzchała & Szymon Rybczak
• Visualizing the Dual-Thread Model of Lynx JS by Łukasz Chludziński
• Why You Don’t Have to Minify JavaScript Code in React Native Apps by Davyd Narbutovich
• Profiling MLC-LLM’s OpenCL Backend on Android: Performance Insights by Artur Morys-Magiera
• How to Cleanly Swap Between React Native Storybook 10 and Your App by Daniel Williams
• Mobile vs. VR: Key Differences in Features, UI, and UX by Jan Jaworski

Podcasts, talks and interviews

• A (Secure) Christmas Carol: The Story of Npmezer Scrooge by Aleksandra Desmurs-Linczewska
• Beyond Static vs. Dynamic: Next.js's New Unified Model by Łukasz Chludziński & Aurora Scharff Aurora Scharff (Crayon Consulting) explains how Next.js is moving to a unified model that ends the static/dynamic split and helps developers manage Suspense boundaries.
• From Hobby Tool to Default: Expo's Journey and the New App Awards by Łukasz Chludziński & Jon Samp Jon Samp (Expo) discusses the framework's evolution since becoming the React Native default, the death of the "eject" mentality, and the launch of the Expo App Awards.
• Testing Native Modules Reliably With JavaScript by Michał Pierzchała Learn how React Native Harness bridges the gap between mocking and E2E testing: real device tests, full native access, Jest-style simplicity.
• React Everywhere: Bringing React Into Native Apps by Mike Grabowski Most teams use React on the web but still rely on native code or WebViews in their mobile apps. This talk explores how React Native can replace WebViews with minimal effort, allowing React to power both web and mobile.

Live Streams

• Building iOS Live Activities with React recording
• React Native 0.83: A Stability-Focused Release With Surprisingly Big Quality-of-Life Wins recording

Upcoming events: React Universe Meetup x Zalando

On January 29, 2026, together with Zalando, we’re hosting the first event of 2026: React Universe Meetup x Zalando in Berlin.

Join us to hear lessons from the early adoption stage of building a responsive video experience at Zalando, running LLMs locally on mobile devices in React Native apps, and hacking your health and productivity with React Native.

That’s it for the December edition. Hope you’re off to a great start to the year. Let's catch up online or in real life!

‍