Callstack
From Native to React Native for TV The Zattoo Case
updated
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Whether you want hot takes, handy tools, or just to watch real devs talk through real things, this stream’s got you covered. Come for the code, stay for the commentary, and bring your own spicy opinions.
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In this episode of React Universe On Air, recorded live at React Universe Conf 2025, host Łukasz Chludziński ( https://x.com/lukasz_app ) sits down with Joel Arvidsson ( https://x.com/trastknast ), Jay Meistrich ( https://x.com/jmeistrich ), and Thibault Malbranche ( https://x.com/titozzz) to unpack the hottest debates and wisest insights from the Core Contributor Summit.
They dive into:
➡️ How the cooperation between consultancies, big organizations like Meta or Microsoft, and OSS contributors looks like
➡️ 2025 as the “year of stability” for React Native
➡️ The promise (and pain) of React Native for desktop apps
➡️ Flipper’s decline and new community-driven DevTools
➡️ Whether React Native 1.0 is just a marketing label or a true milestone
➡️ How agencies and individuals balance open source with client work
➡️ Practical advice for engineers who want to contribute and join the conversation
Chapters:
00:00 Welcome to the React Universe
01:21 Meet our guests: Thibault Malbranche, Joel Arvidsson, Jay Meistrich
02:33 What is Core Contributor Summit
04:02 Meta vs. community usage of React Native
07:19 Year of stability & tooling challenges
09:00 Surprise session: React Native for Desktop
16:10 Concrete outcomes vs. planting seeds
21:02 Open Source dynamics & collaboration
27:30 React Native 1.0
33:45 Future directions & getting involved
36:50 Final thoughts
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At React Universe Conf 2025, Marc Rousavy (CEO at Margelo, creator of VisionCamera and MMKV) traces the story of Nitro: from its origins in JSI experiments to its role in powering high-performance libraries like react-native-filament, MMKV, and soon VisionCamera.
Skip the intro ⏩ 0:39
🔹 Lessons learned from early JSI host objects in MMKV and VisionCamera
🔹 Why boilerplate, threading issues, and crashes led to building Nitro
🔹 How Nitro simplifies bindings with strong typing, thread safety, and code generation (Nitrogen)
🔹 Using Nitro to bridge C++, Swift, and Kotlin seamlessly
🔹 Nitro’s growing ecosystem: Nitro Image, MMKV rewrite, Filament, and more
🔹 What the future holds as VisionCamera is migrated to Nitro
In short, this talk shows how Nitro is shaping the next generation of native modules.
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At React Universe Conf 2025, Adam Mruk (Senior Engineer at Klarna) takes us behind the scenes of building an in-house OTA solution serving 100M+ users across iOS, Android, web, and browser extensions. Drawing on Klarna’s experience, he reveals why “just pushing a new bundle” is only the beginning.
Skip the intro ⏩ 0:39
🔹 Why OTA can only ship JavaScript updates, not native code
🔹 Klarna’s custom OTA architecture: backend services, artifact storage, and client rollout control
🔹 Using Re.Pack for code splitting and Script Manager for bundle loading
🔹 Diff-based updates to shrink payloads from tens of MBs to hundreds of KBs
🔹 Reliability techniques: health checks (“dead on arrival”), rollback strategies, checksum validation
🔹 Real-world pitfalls with Hermes bytecode diffs, asset resolution on iOS, and rollout percentages
🔹 Why “instant” updates aren’t truly instant and how analytics and monitoring must adapt
This talk cuts through the hype and shows what it really takes to implement robust OTA updates in React Native at scale.
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At React Universe Conf 2025, Rene Eichhorn (Senior Software Engineer at Zalando) shares the technical details and architectural lessons from Zalando’s ongoing React Native migration. The talk highlights both the challenges of brownfield integration and the strategies that make large-scale adoption possible.
Skip the intro ⏩ 0:39
🔹 A non-standard brownfield integration strategy that enables progressive adoption without rewriting half a million lines of native code
🔹 Building a React Native framework package for iOS and Android, enabling seamless interoperability with existing native apps
🔹 Using React Strict DOM as a foundation for future web and mobile unification
🔹 Extending React Native with Zalando’s internal React framework to establish shared patterns across web and mobile
🔹 Balancing cross-platform code sharing with platform-specific differences to preserve native UX
🔹 Lessons learned about experimentation, A/B testing, and scaling React Native to support hundreds of engineers
This deep dive shows how Zalando is bridging the gap between web and mobile, unifying development practices, and bringing React Native to enterprise scale.
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🎤 React Universe Conf: venue, merch, vibe, and presentations with guest Szymon
🤖 AI rant from Kewin: what to watch out for & why AI is never objective
📦 React Native 1.0: what it really means, release cycle improvements, and the Nightly program
🚀 Expo updates: beta support for Xcode 26 in EAS, autolinking fixes, and our take on the Expo landscape
⚡ RN ecosystem moves: documenting native APIs, Legacy Arch removal
💡 Plus side chats on setTimeout/setInterval, Nitro & Turbo Modules, Expo migrations, and JSI bindings
Don’t miss out; catch the full session for all the insights, demos, and discussions!
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Featuring:
- Charlie Cheever (CEO, Expo)
- Mike Grabowski (CTO & Founder, Callstack)
- Nicola Corti (React Native Core Team, Meta)
- Tom Occhino (Chief Product Officer, Vercel)
- Christoph Nakazawa (CEO, Nakazawa Tech)
- Michał Pierzchała (Principal Engineer, Callstack)
Skip the intro ⏩ 0:39
Our panelists discuss:
🔹 Key milestones and turning points from React Native’s first 10 years
🔹 What worked, what didn’t, and what was learned along the way
🔹 How AI and intelligent coding agents are reshaping the developer workflow
🔹 Opportunities and challenges for React Native in the next decade
🔹 Predictions for the future of cross-platform development
This candid panel explores both the history and the horizon of React Native: where it’s been, and where it’s going.
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Featuring:
- Chris Trag (Head of Evangelism, Amazon)
- Kadi Kraman (Software Developer, Expo)
- Danny Williams (Maintainer, React Native Storybook)
- Mo Gorhom (Senior Software Engineer, Amazon & OSS maintainer)
- Khalef Hosany (Principal Engineering Manager, Microsoft)
Skip the intro ⏩ 0:39
Our panelists discuss:
🔹 The reality of “learn once, write anywhere” after 10 years of React Native
🔹 Code sharing percentages: how much is realistic, and where native code still matters
🔹 Platform-specific trade-offs: mobile vs. web vs. desktop vs. TV
🔹 Supporting multiple input modes, screen resolutions, and performance constraints
🔹 Brownfield challenges and bridging native functionality at scale
🔹 Testing strategies: emulators vs. device banks and progressive rollouts
🔹 How AI and automation are changing multi-device React development
The panel closes the conference with candid insights, spicy takes, and practical advice from engineers building React apps for every screen.
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Skip the intro ⏩ 0:39
🔹 Mike reflects on React Native’s evolution from its early beginnings to today’s global scale, powering millions of apps and 30% of top finance apps worldwide.
🔹 Riccardo introduces 2025 as the “Year of Stability,” unveiling predictable release cycles, stable APIs, Android 16 support, iOS build performance improvements, and a call to migrate fully to the new architecture.
🔹 Michał looks forward, presenting Rock, Callstack’s React Native enterprise framework, and a broader ecosystem of tools for scaling apps, securing microfrontends, and advancing cross-platform development.
This keynote sets the tone for React Native’s next decade of growth: stability, scalability, and an ecosystem ready for enterprise adoption.
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At React Universe Conf 2025, Tomasz Żelawski (Software Engineer at Software Mansion) introduces react-native-worklets, a library that enables developers to push JavaScript to its multithreading limits. Worklets unlock new levels of performance by allowing concurrent execution outside the main JS thread, reducing bottlenecks and enabling smoother, more responsive apps.
Skip the intro ⏩ 0:39
🔹 Why single-threaded JavaScript is limiting in React Native
🔹 How react-native-worklets enables concurrent execution across multiple threads
🔹 Practical examples of using worklets everywhere, from UI interactions to heavy computations
🔹 Internals and implementation quirks developers should know before adopting worklets
🔹 The future of concurrency in React Native and how worklets fit alongside the new architecture
This talk is a deep dive into the mechanics of concurrent JavaScript in React Native and why worklets are a game-changer for performance.
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At React Universe Conf 2025, Aurora Scharff (Web Developer & Consultant at Crayon Consulting) explores how modern React patterns address common async challenges like unstable interfaces and inefficient state updates.
Skip the intro ⏩ 0:39
🔹 How concurrent rendering features (`useTransition`, `useDeferredValue`, `useOptimistic`) solve flickering pending states and race conditions.
🔹 Using Actions in React 19 for async workflows with built-in optimistic updates and predictable pending states.
🔹 Practical examples in the Next.js App Router: server components for streamlined data fetching, plus reusable “router-aware” UI components.
🔹 Coordinating async behavior across components with Actions for custom UI feedback like progress bars, toasts, and even confetti 🎉.
🔹 Looking ahead to View Transitions: integrating animations with concurrent features to create fluid, intentional visual updates.
You’ll leave with a clear roadmap for building reusable, async-safe React components while ensuring smooth and reliable user experiences.
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At React Universe Conf 2025, Violina Popova (Software Developer at ClipMyHorse.TV) shares how her team uses A/B testing in React Native to move from intuition-driven development to truly data-driven decision-making.
Skip the intro ⏩ 0:39
🔹 How ClipMyHorse.TV discovered that removing free trials increased paid subscriptions by 25%
🔹 Designing meaningful experiments: from hypotheses to control and variant groups
🔹 Tools for React Native A/B testing, including Firebase Remote Config for rollout control
🔹 Handling challenges like app store delays, gradual rollouts, and feature kill switches
🔹 Avoiding common pitfalls: starting too big, ignoring significance, and forgetting to clean up old experiments
🔹 How a culture of continuous experimentation improved app ratings from ~2.5★ to over 4.5★
This talk shows how experimentation transforms products, helping developers validate ideas, reduce risk, and build features that truly matter to users.
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At React Universe Conf 2025, Artur Morys-Magiera and Dominik Dolny (Senior Engineers at Callstack) introduce Ottrelite, a unified and extensible tracing framework for React Native. Ottrelite re-enables the existing Systrace JS API through Nitro Modules and provides a plugin system for plugging in any native tracing backend.
Skip the intro ⏩ 0:39
🔹 Why tracing React Native internals has been difficult with prebuilt artifacts and missing plugin support
🔹 How Ottrelite avoids building React Native from source while still enabling deep instrumentation
🔹 Support for multiple languages: JavaScript, Kotlin/Java, Swift/Objective-C, and C++
🔹 Built-in backends: Tracy, Android ATrace, and iOS os_signpost, plus the ability to bring your own
🔹 Development vs. production workflows: profiling with Tracy, telemetry with OpenTelemetry and tools like Grafana, Jaeger, or Prometheus
🔹 Automatic component instrumentation with a Babel plugin, plus hooks for custom tracing and metadata
Ottrelite bridges the gap between React Native DevTools and modern observability needs, making it easier than ever to trace, profile, and monitor apps across platforms.
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At React Universe Conf 2025, Matt Pocock (Author of Total TypeScript) gives a hands-on crash course in AI SDK v5, showing how to integrate AI into React apps while avoiding vendor lock-in.
Skip the intro ⏩ 0:39
🔹 Why you should learn AI “from the outside in” by building apps, not studying internals
🔹 How the AI SDK provides one unified API for OpenAI, Anthropic, Google, Mistral, local models, and more
🔹 Using `generateText`, `generateObject`, `streamText`, and `streamObject` for powerful and type-safe workflows
🔹 Preventing model lock-in with simple provider swaps in a single line of code
🔹 Streaming results for faster time-to-first-token and real-time UI updates
🔹 Building AI agents with type-safe tool calls using Zod schemas
🔹 Why AI SDK v5 is more than a gateway; it’s a highway to production-ready AI apps
If you’re a TypeScript developer looking to bring AI into your applications, this is the talk you’ve been waiting for.
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At React Universe Conf 2025, Zackary Chapple (CEO at Zephyr Cloud) shows how Module Federation in Re.Pack 5 brings the proven patterns of distributed web development to React Native. With millions of downloads a week, Module Federation is the de facto standard for decomposing apps on the web, and now it’s available for mobile.
Skip the intro ⏩ 0:39
🔹 How to decompose React Native apps into independent modules
🔹 Giving teams autonomy with separate release cycles and versioning
🔹 Practical strategies for managing module versions and shipping updates independently
🔹 A comparison of OTA (over-the-air) update solutions and why module-level distribution is different
🔹 How Module Federation enables instant rollbacks and even testing in production at scale
From monolithic releases to actually distributed mobile development, this talk explores how Module Federation changes the way we build, version, and release React Native apps.
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At React Universe Conf 2025, Dr. Kubilay Ahmet Küçük (Computer Scientist, Oxford University) introduces cpp.js.org: a practical, automated toolset for seamlessly integrating modern C++ libraries into React Native and WebAssembly projects. Designed for both enterprise scalability and developer productivity, cpp.js minimizes the manual work of compiling, porting, and bridging libraries to JSI.
Skip the intro ⏩ 0:39
🔹 Why current bridging solutions fall short, and how cpp.js provides a long-term, maintainable alternative
🔹 Writing and executing native C++ code directly inside a JavaScript environment
🔹 Importing ready-to-use C++ libraries from the cpp.js repository with just a header include
🔹 Porting your own C++ libraries, even those with external dependencies, using cpp.js automation
🔹 Real-world integrations, including GIS libraries like GDAL, and performance benchmarks showing native-level speed
🔹 Cross-platform support: React Native, WebAssembly (web, Node.js, Cloudflare Workers), mobile, backend, and cloud
With C++11/14 OOP support, automation for long-term maintenance, and practical tooling, cpp.js offers the React Native community a stable, scalable way to bring the full power of C++ into JavaScript applications.
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At React Universe Conf 2025, D. Richard Hipp (creator of SQLite) explores how SQL database engines implement a form of automatic programming: taking your problem statement and generating the algorithms and execution code for you.
Skip the intro ⏩ 0:39
🔹 Why SQL qualifies as AI, and how it compares to large language models
🔹 How SQL compilers translate declarative queries into optimized execution plans
🔹 Examples showing multiple possible algorithms for a query, and how the engine selects the best one in microseconds
🔹 Why advanced optimizations in SQL engines solve NP-complete problems on your behalf
🔹 How leveraging SQL as an AI assistant can boost productivity and accuracy while preventing “reinventing the wheel” with custom code
🔹 Practical guidance: when to use embedded engines like SQLite vs. client–server databases like Postgres or MySQL
SQL has been writing code for us all along. This talk reframes SQL as the AI assistant you already have, and shows why mastering it is key to long-term developer productivity.
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At React Universe Conf 2025, Kræn Hansen (Senior Software Engineer at MongoDB) shares the latest progress on bringing Node-API to React Native. Node-API, long used in Node.js and other runtimes, offers an ABI-stable boundary for native modules, unlocking big improvements in React Native developer experience.
Skip the intro ⏩ 0:39
🔹 Super-fast calls between JavaScript and native code written in C++, Rust, or other FFI-enabled languages
🔹 Prebuilt (ahead-of-time compiled) libraries thanks to Node-API’s ABI-stable C interface
🔹 Unit tests that run against the same native code in both Node.js and React Native
🔹 The `react-native-node-api-modules` package for lazy-loading prebuilt dynamic libraries
🔹 Progress on landing Node-API support in Hermes and improving prebuild tooling across platforms
This talk highlights how Node-API can reduce friction for app developers and library authors, while opening the door to cross-runtime, type-safe, and faster React Native development.
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At React Universe Conf 2025, Szymon Chmal (Senior Software Engineer at Callstack) introduces Rozenite: a framework designed to bring a robust plugin system back to React Native DevTools. Built on top of the existing architecture, Rozenite makes it possible to extend DevTools without forking or hacks.
Skip the intro ⏩ 0:39
🔹 Why Flipper’s plugin system mattered and how its absence in DevTools creates a gap for developers
🔹 How Rozenite hooks cleanly into DevTools communication without breaking stability
🔹 Building plugins with sandboxed execution and React-based UIs inside DevTools
🔹 Official plugins available today: Redux DevTools, TanStack Query, network activity monitoring, performance marks, and more
🔹 How you can build your own plugins for state machines, analytics, feature flags, or any internal app logic
🔹 What’s next: Rozenite 1.0 and a growing ecosystem of community-driven plugins
Whether you need better debugging tools for your own app or want to share plugins with the React Native community, Rozenite makes DevTools truly extensible again.
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At React Universe Conf 2025, Anisha Malde (Developer Evangelist at Amazon) explores the “generations of React” and how different learning journeys influence developer habits and best practices.
Skip the intro ⏩ 0:39
🔹 The Class Component Generation: understanding lifecycle methods and the discipline of explicit structure.
🔹 The Hooks Generation: learning React post-2020 with new flexibility, but also new pitfalls like overusing `useEffect` and `useMemo`.
🔹 The Compiler Generation: a new wave of developers leaning on AI and compiler optimizations, sometimes without grasping fundamentals.
🔹 How differences in starting points affect state management choices, library preferences, and performance trade-offs.
🔹 Why knowing the fundamentals of React’s lifecycle and mental models makes you more effective; especially on constrained devices like Fire TV.
Whether you started with classes, hooks, or compilers, this talk is a reminder that fundamentals never go out of style.
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At React Universe Conf 2025, Xuan Huang, Ziqi Zhen, and Haoyang Wang from ByteDance introduce React for two threads, a paradigm shift in how React applications can be built and executed.
Skip the intro ⏩ 0:39
🔹 The tradeoffs of React’s single-threaded model, and why it limits performance.
🔹 A dual-thread approach that enables instant first-frame rendering, reduced interaction latency, and smoother animations.
🔹 New abstractions like Main Thread Functions (MTFs) and Main Thread Components (MTCs) that bring synchronous UI updates and full reactivity back to the main thread.
🔹 Real-world demos: from sliders to color pickers, showing how responsiveness improves when event handling is split intelligently across threads.
🔹 Lynx: ByteDance’s production-ready framework implementing the two-thread model, already powering TikTok features, and now extended to the web using Web Workers.
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At React Universe Conf 2025, Vladimir Morozov and Khalef Hosany from Microsoft share how they’ve integrated Hermes with Node API, and what this means for the future of React Native.
Skip the intro ⏩ 0:39
🔹 What Node API is, why ABI stability matters, and how it enables long-term module compatibility.
🔹 How React Native Windows adopted Node API to support multiple engines and languages.
🔹 A fork of Hermes reimplementing JSI on top of Node API, and the path to upstreaming this work.
🔹 Demos showing Node API modules compiled once and running across different environments, including Hermes.
🔹 What this unlocks: universal native modules, cross-runtime portability, and using the latest Hermes with older React Native versions.
This talk highlights how the combination of Hermes and Node API creates a more stable, extensible, and future-proof foundation for React Native development.
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In this talk from React Universe Conf 2025, Jay Meistrich (Founder of Legend, CTO of Bravely) shares the core optimizations behind Legend List v2, the fastest list implementation for React Native and React DOM. Many of the optimizations, like signals and minimizing renders, are shared across platforms, but there are also key differences in how lists are measured, ordered, and rendered on the web.
Skip the intro ⏩ 0:39
🔹 How container recycling and minimizing renders improve performance on mobile and web
🔹 Why MVCP (Maintain Visible Content Position) is critical for smooth scrolling and accurate `scrollToIndex`
🔹 Differences between React Native and web implementations, from DOM reordering to GPU limits
🔹 General optimization tips and tricks for making React apps scroll faster and feel more responsive
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In this talk from React Universe Conf 2025, Ohans Emmanuel (Staff Software Engineer at HelloFresh) shares a real-world journey of using GenAI coding agents to automate and accelerate the conversion of web components into native mobile UI.
Skip the intro ⏩ 0:39
🔹 The challenge of migrating a massive codebase with 10,000+ React components, including a critical Product Card with 13k lines of code.
🔹 Why naive “one-shot” AI conversions fail, and how to work around large contexts, complex states, and deterministic requirements.
🔹 Techniques like selective context, breaking work into smaller agent tasks, and enforcing deterministic states with TypeScript.
🔹 Building self-correcting agentic flows: having agents write failing tests first, validate implementations, and iterate until outputs matched expected APIs and UI.
🔹 How these methods reduced weeks of manual migration work to just hours, while improving consistency across platforms.
A practical, battle-tested case study of how GenAI can meaningfully accelerate cross-platform React Native adoption.
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At React Universe Conf 2025, Jacek Pudysz (CTO & Co-Founder at Codemask) takes us deep into the internals of React Native’s styling pipeline and shares the ongoing mission behind Unistyles.
Skip the intro ⏩ 0:39
🔹 How styles flow from JavaScript down to C++ and platform-specific layers through Fabric and JSI.
🔹 Why React Native’s built-in `StyleSheet` can be considered the true baseline of “zero-cost” runtime styling.
🔹 How Unistyles pushes beyond developer experience, using a C++ core and Nitro Modules to skip re-renders and recompute styles natively.
🔹 Benchmarks showing the performance gap between Unistyles and the native `StyleSheet`, and why the hunt isn’t over.
🔹 A look ahead at Uniwind, a new Tailwind-inspired runtime styling library for React Native, designed to deliver advanced features with near-`StyleSheet` performance.
This talk reveals both the engineering challenges and future opportunities of runtime styling in React Native, showing why the quest for zero-cost styling continues.
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At React Universe Conf 2025, Christoph Nakazawa (CEO of Nakazawa Tech, creator of Jest, former React Native lead) shows how to cut through the noise and build apps end-to-end with speed, stability, and good defaults.
Skip the intro ⏩ 0:39
🔹 What “scalability” really means: fast to build, fast to deploy, fast for users.
🔹 The principle of global order, local chaos; keeping the system clean while teams move fast.
🔹 Why building on open source defaults beats reinventing the wheel.
🔹 A modern app template that includes type safety, testing, styling, and internationalization out of the box.
🔹 How backend templates with GraphQL and Prisma enable type-safe data flows from database to client.
🔹 Relay integration for declarative data fetching and composable fragments that maximize local reasoning.
From Expo apps to GraphQL servers to publishing packages, Christoph demonstrates how good defaults and open source tooling let you focus on your product instead of endless setup decisions.
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At React Universe Conf 2025, Fernando Rojo, Head of Mobile at Vercel, demonstrates how composition can scale your codebase from a single component to thousands, while making it easier for both humans and AI to work in.
Skip the intro ⏩ 0:39
🔹 Why “boolean prop hell” (e.g. `isEditing`, `shouldRenderButton`) makes components unmaintainable.
🔹 How real-world UIs like Slack’s composer quickly become messy when built with conditional props.
🔹 A compositional approach that replaces bloated monoliths with small, flexible components.
🔹 Techniques for handling state management, whether ephemeral (local) or global (synced across devices).
🔹 How composition makes codebases more AI-friendly, enabling developers to pair program effectively with AI tools.
🔹 A special live AI prompt to close the talk.
If you’ve ever wrestled with sprawling conditionals and rigid components, this talk will help you fall in love with React again.
See you at another React Universe Conf 🎟️ clstk.com/4m4dxn4
Follow React Universe Conf on X to stay up to date 🐦 https://x.com/reactuniverse_
Check out Callstack content 📚 clstk.com/41IqFHl
At React Universe Conf 2025, Jorge Cohen, Engineering Manager on the React team at Meta, unveiled a strategic overhaul of the React Native release process. This talk dives deep into how Meta is making React Native more predictable, stable, and developer-friendly than ever before.
Skip the intro ⏩ 0:39
🔹 Why React Native upgrades earned a bad reputation, and how that’s changing.
🔹 The shift from 2 releases a year → 6 predictable releases a year, shipped on time, every two months.
🔹 Automation with bots and GitHub Actions to cut human error and reduce release crew workload.
🔹 New end-to-end testing, nightly builds, and ecosystem-wide compatibility checks.
🔹 Clear support windows and fewer breaking changes to make upgrades simple and boring (in a good way).
🔹 A look ahead to the path towards React Native 1.0.
If you’ve ever dreaded an upgrade, this talk will show you how React Native is building a stable foundation for the next decade.
See you at another React Universe Conf 🎟️ clstk.com/42cLgUm
Follow React Universe Conf on X to stay up to date 🐦 https://x.com/reactuniverse_
Check out Callstack content 📚 clstk.com/4phFTNO
Key topics covered:
• Rock (formerly RNEF) setup and scaffolding
• Publishing a React Native module as an AAR
• Gradle configuration for integration
• Host initialization in Android
• Embedding React Native fragments
Download the free guide on Incremental React Native Adoption in Native Apps 📘 clstk.com/3JFgvkC
Let’s discuss your brownfield adoption needs ⚡ clstk.com/421Dw7A
Follow Callstack on X 🐦 https://x.com/callstackio
More talks, more cross-platform insights, and more reasons to rethink how we build with React and React Native.
Today’s stream includes advanced sessions, fresh takes on developer tooling, and another round of live studio coverage: interviews, panels, and behind-the-scenes access with the people driving the React ecosystem forward.
Stick around for big ideas and practical takeaways you won’t hear anywhere else.
Let’s keep the conversation going at React Universe Conf’s X 🐦 https://x.com/reactuniverse_
Find out more about Callstack, the conference’s organizer ⚛️ clstk.com/3JFFjsF
Expect deep dives into full-stack development, cutting-edge cross-platform strategies, and the tools shaping tomorrow’s apps. Between sessions, tune into our live studio featuring exclusive interviews, dev panels, and a live podcast episode.
Let’s keep the conversation going at React Universe Conf’s X 🐦 https://x.com/reactuniverse_
Find out more about Callstack, the conference’s host ⚛️ clstk.com/4695oJs
➡️ Nuqs 2.5 in action
➡️ Saw how easy it is to keep state in search params.
➡️ Demoed it live, and wow, we were so impressed we didn’t get to the updates like debounce, schemas, key isolation, and type-safe routing.
➡️ Remix vs. App Router, React Router & Expo Router: We compared their approaches, strengths, and where each one shines.
➡️ Web Workers vs. Worklets: A short dive into how they’re alike, and why web workers are becoming a smart move for performance-focused devs.
➡️ Expo launch: Expo just launched a cool new initiative that streamlines app release workflows. No DevOps headache required, just build and ship like a pro.
➡️ SPM support & why pre-compilation wasn’t in React Native: We chatted about Swift Package Manager support and tackled the big question: why didn’t React Native include pre-compilation from day one? Mike jumped in with insights from a decade in the game.
➡️ Jest Split RFC & the Vite Sweepstakes: Separating Jest from RN core? Smart. Naturally, we couldn’t help but gush about Vite, too
➡️ Text-to-Speech & Speech-to-Text with React Native AI: We wrapped with a deep dive into native voice features, Mike’s building it, and it’s worth watching.
See you at other Callstack live streams and events ✨ clstk.com/474kFw4
Check out more content from Callstack 📚 clstk.com/45MD1Q4
Follow Callstack on X 🐦 https://x.com/callstackio
In this walkthrough, Burak Güner (https://x.com/_atlj) shows how to:
• Spin up a Rock (formerly known as React Native Enterprise Framework, or shortly RNEF) project configured for iOS
• Export React Native modules as XCFrameworks
• Import and initialize React Native in a SwiftUI app
• Replace a native view with a React Native screen
By the end, you’ll understand how to extend an existing iOS app with React Native in a controlled, incremental way.
Link to Github repository: github.com/callstack-internal/rock-brownfield-example
Download the free guide on Incremental React Native Adoption in Native Apps 📘 clstk.com/3UNvpaU
Let’s discuss your brownfield adoption needs ⚡ clstk.com/3JzRYNV
Follow Callstack on X 🐦 https://x.com/callstackio
Observability isn't a luxury; it's the feedback loop your app depends on.
In the latest podcast episode, we discuss spans, logs, metrics, real user monitoring, and all things observability and OpenTelemetry-related 👉 youtu.be/DpHza-0R0mg
We also cover:
- Next.js 15.5 updates (TS in app routes, Node.js middleware, TurboPack)
- RNEF rebrands to Rock
- How SVGs actually work (with help from Josh W. Comeau)
- The mega-edition of “This Week in React”
See you at other Callstack live streams and events ✨ clstk.com/4fF7y6V
Check out more content from Callstack 📚 clstk.com/3JdICHw
Follow Callstack on X 🐦 https://x.com/callstackio
Highlights from this week’s stream:
⚛️ React Native 0.81
👉 Prebuilt iOS binaries cut build times from ~200s → 20s
👉 Android 16 (API 36) is now the default target
👉 SafeAreaView deprecated
👉 Community-maintained JSC from Callstack & Expo
⚛️ Other dev news
👉 Xcode management made easy
👉 How a 5-year-old design decision still shapes web colors
👉 Oracle vs Deno: the “JavaScript” trademark fight
👉 GitHub joins Microsoft’s CoreAI team
Drop your thoughts in the comments 💬 Is RN 0.81’s prebuild feature a game-changer for your workflow?
See you at other Callstack live streams and events ✨ clstk.com/4fMgc3D
Check out more content from Callstack 📚 clstk.com/4fsG2sV
Follow Callstack on X 🐦 https://x.com/callstackio
In this episode of React Universe On Air, Łukasz Chludziński sits down with Jonathan Munz (Senior Software Engineer at Embrace) and Adam Horodyski (React Native Expert at Callstack) to unpack how OpenTelemetry can bring structure and clarity to mobile monitoring.
They break down why mobile observability is harder than observability on backend, what the OTLP protocol enables, and how to instrument React Native apps without locking into a single vendor. You’ll also hear how community-driven tooling like React Native OpenTelemetry and the Embrace React Native SDK can simplify setup and improve data portability.
You’ll learn:
➡️ How observability and OpenTelemetry work together
➡️ The 3 core OpenTelemetry signal types for mobile
➡️ Why mobile instrumentation is more complex than backend telemetry
➡️ How OTLP improves interoperability between tools
➡️ Where auto-instrumentation is still missing in React Native
➡️ The role of Embrace and open-source libraries in reducing setup overhead
Check out episode resources on our website 📚 clstk.com/4104nAF
Catch more React Universe On Air episodes 🎧 clstk.com/45EWnYe
Monitor what matters in your React Native app with Callstack’s help 🤝 clstk.com/3HoM3KI
Sign up for our newsletter ✉️ callstack.com/newsletter
Follow us on X 🐦 https://x.com/callstackio
Chapters
00:00 Welcome to the React Universe
01:07 Meet our guests
03:07 Defining observability and OpenTelemetry
04:32 Signals in observability
11:57 Challenges with observability in React & React Native
16:04 Standardization and OpenTelemetry protocol
18:08 Embrace and OpenTelemetry
21:29 Future of OpenTelemetry in mobile
27:23 Exploring React Native OpenTelemetry
29:54 Community involvement in OpenTelemetry
37:34 Real observability in React Native
46:41 Future of React Native observability
50:40 Hey, listeners, here’s what we want you to do
54:46 Conclusion and final thoughts
🚀 FlashList v2: Shopify’s high-performance list library for React Native gets a major upgrade. Say goodbye to estimated sizes and native layout patches; v2 is smoother, smarter, and more accurate.
🧠 Vercel AI SDK 5: The latest version of Vercel’s AI SDK introduces speech generation, better agentic workflows, type-safe tool usage, and a fully restructured `useChat` hook. It's rapidly becoming a frontend-friendly toolkit for building LLM-powered apps.
We also cover:
👉 Matt Pocock’s upcoming AI SDK workshop at React Universe
👉 The React Compiler’s new directives (`use memo`, `use no memo`) and its path to stable release
👉 Next.js 15.4 reaching full Turbopack compatibility for production builds
👉 React Native Sandbox from Callstack for secure, isolated mini-apps
👉 A deep dive into the past decade of JavaScript runtimes and engines
See you at other Callstack live streams and events ✨ clstk.com/45uc1pj
Check out more content from Callstack 📚 clstk.com/4l4FiLS
Follow Callstack on X 🐦 https://x.com/callstackio
Join Mike Grabowski (Callstack) and Keith Kurak (Expo) for a dev-focused walkthrough on how to incrementally adopt Expo without rewriting your app.
✅ Learn when and how to integrate Expo modules
✅ See how EAS Build simplifies your native CI/CD
✅ Understand how Expo SDK supports complex native features
✅ Explore real strategies and pitfalls to avoid during migration
Why watch this?
➡️ You’ll get a clear migration path for modernizing your React Native setup
➡️ You’ll understand the real advantages Expo brings to performance, tooling, and dev workflow in 2025
➡️ You’ll hear directly from two core contributors shaping the React Native ecosystem
Need help migrating to Expo? Get expert help from Callstack 🙌 clstk.com/4m9RgW6
Check out more Expo content from Callstack 📚 clstk.com/3GXMKe0
For more content like this, follow us on X 🐦 https://x.com/callstackio
Links from the webinar:
Incremental Expo Adoption Blog: https://expo.dev/blog/how-to-incrementally-adopt-expo
Adoption Pull Requests: github.com/keith-kurak/GraduallyAdoptExpo2025/pulls?q=sort%3Aupdated-desc+is%3Apr+is%3Aclosed
Continuous Native Generation: https://expo.dev/blog/what-is-continuous-native-generation
Get a combo ticket now to secure your spot at the workshop and conference 🎟️ clstk.com/4moA2DT
We explore:
➡️ Rozenite, the new framework for building custom React Native DevTools plugins, with 4 plugins ready: Network, TanStack Query, Redux, and Expo Atlas.
➡️ Precompiled React Native for iOS (0.81), bringing up to 10x faster builds and a major productivity boost for iOS developers.
➡️ On-device AI with Apple NLP, enabling local text embeddings for privacy-friendly and offline-ready ML features.
➡️ TanStack DB 0.1, an embedded client-side database designed to pair seamlessly with TanStack Query.
➡️ React Core update, deprecating the "throw a Promise" pattern (used in react-freeze), marking another step in the evolution of React Suspense.
Watch the full replay for code-level insights, live demos, and real-world implementation tips.
See you at other Callstack live streams and events ✨ clstk.com/453fI45
Check out more content from Callstack 📚 clstk.com/3UwoDWE
Follow Callstack on X 🐦 https://x.com/callstackio
1️⃣ agenda with some real heavy-hitter talks incoming (he breaks it down in the video)
2️⃣ A promo code to save you money
Regular pricing ends today, so this is the best deal you’ll get 👀 Get your ticket at clstk.com/40ERaNu
In the recent podcast episode, we discussed how slow builds, flaky tests, and siloed teams all traced back to a polyrepo setup.
Monorepo changed the game to faster releases, lower infra costs, and better dev retention.
Full episode here ➡️ youtu.be/9OqzGMWHZTA?feature=shared
We explore:
- How Reanimated 4 simplifies animations using a CSS-like syntax and reduces the need for boilerplate useAnimatedStyle code.
- Why the newly separated Worklets library enables off-thread execution, freeing up the main JS thread for smoother gestures and transitions.
- Enhancements in React Native Screens, including native bottom tabs and split view on iPadOS.
- What’s new in Keyboard Controller 1.8.0, and how it makes customizing views around the keyboard more robust.
- A new way to distribute signed iOS builds; Fastlane-style, no Ruby required.
Watch the full replay for code-level insights and practical implementation tips.
See you at other Callstack live streams and events ✨ clstk.com/44PMgyf
Check out more content from Callstack 📚 clstk.com/4eTgepH
Follow Callstack on X 🐦 https://x.com/callstackio
The highlight? Łukasz gave a developer-friendly breakdown of Node-API support in React Native: what it is, why it matters, and what you can actually do with it today. If you’re up for a full 3-hour deep dive, watch it here: youtube.com/live/uN6rCaJMPzI?feature=shared
Other dev-eye-openers from Week 29:
- `react-native-wallet`: Now you can add payment cards to Apple & Google Wallets from RN apps. Expensify & Software Mansion nailed it.
- `react-native-worklets`: A new library extracted from Reanimated. What does it do? Can it co-exist with Margelo’s version? The devs discuss.
- ChromeOS + Android convergence: What’s Google planning? Kewin and Łukasz speculate on dev implications.
- On-device Apple LLMs in React Native: Native LLM, offline. React Native just got smarter.
- TinyBase: A slick, reactive, local-first data store with new RN support via `persister-react-native-sqlite`.
- React Native Enterprise Framework 0.8: The new release comes with a new CLI visual style, RN 0.80 support, and works with RNC CLI 19.1.
- Metro + Module Federation: A Callstack-led effort to bring modularity to the Metro bundler. Re.Pack, but native.
See you at other Callstack live streams and events ✨ clstk.com/468NHKt
Check out more content from Callstack 📚 clstk.com/44LB0Ts
Follow Callstack on X 🐦 https://x.com/callstackio
In this episode of React Universe On Air, Łukasz Chludziński ( https://x.com/lukasz_app ) chats with Jordan Powell ( https://x.com/JordanPowell88 ) from Nx to explore what it really takes to build and manage a monorepo at scale. From dependency graphs to distributed CI tasks, they break down how Nx helps teams stay fast, focused, and frustration-free. Whether you're just getting started with Yarn Workspaces or running into CI bottlenecks, this episode gives you the strategies and context to go further with less overhead.
Key learnings
➡️ The difference between monorepos and monoliths
➡️ How Nx graphs improve selective builds and testing
➡️ What “ownership rules” mean for large codebases
➡️ How distributed task execution saves time in CI
➡️ Why better DX equals better business outcomes
➡️ Real-world patterns for React Native and full-stack monorepos
Check out episode resources on our website 📚
Catch more React Universe On Air episodes 🎧 clstk.com/44Bj51X
Get your React Universe Conf 2025 tickets 🎟 clstk.com/4nFqTZ1
Sign up for our newsletter ✉️ clstk.com/3TrnIGH
Follow us on X 🐦 https://x.com/callstacki
Chapters
00:00 Welcome to the React Universe
00:42 Meet Jordan Powell from Nx
02:42 The joy and pain of testing
04:03 Understanding monorepos
06:52 The origins of Nx
09:41 Developer experience and its business impact
12:10 Nx vs. other tooling and a closer look at its features
21:07 Getting started with Nx
25:27 Collaborating on projects
28:00 Assigning ownership and scoping projects
29:30 Managing dependencies in a monorepo
31:16 Handling multiple framework versions and migrations
32:40 Real-world examples of large-scale monorepos
36:10 Distributed task execution with Nx Cloud
39:08 Efficient testing in a monorepo
42:55 The Future of Nx with AI integration
47:27 Conclusion and final thoughts
In this live session, we break down what Node-API is, what it isn’t, and how to use it in React Native today. You’ll see how to compile and load native code into RN using `react-native-node-api`, understand how it differs from JSI and TurboModules, and explore the long-term vision for precompiled native modules that install via npm.
What you’ll learn:
- What Node-API enables (and what it doesn't) in React Native
- How to use `react-native-node-api` to build and load native logic
- Why this isn’t a drop-in for native UI or Node.js built-ins
- How to ship and distribute native modules as prebuilt binaries
Featuring Kræn Hansen ( https://x.com/kraenhansen ), Mariusz Pasiński ( https://x.com/mani3xis ), and Łukasz Chludziński ( https://x.com/lukasz_app )
Read the Node-API Support for React Native announcement on Callstack blog 📚 clstk.com/40dZrHU
See you at other Callstack live streams and events ✨ clstk.com/3TBrJIC
Follow Callstack on X 🐦 https://x.com/callstackio


