📨 #299: Panda, Vinext, Next.js, Preact, Design Systems, RTK | Variable font, Activity Result, Lynx, Lucent, macOS, Plain Text, Navigation, Angular Native, Re.Pack | TC39, Composites, WebSkills, MSW, upm, pnpm

Hi everyone, Seb and Jan here 👋!

This week we have 2 major releases in the React ecosystem: Panda CSS v2 and Vinext v1.

On the mobile side, RN is getting support for variable font and Android Activity Result. Lynx v4 is out. Lucent is a new way to write native modules.

I’m particularly excited about the TC39 meeting happening right now. Many proposals progressed, including my favorite one: Composites moved to stage 2!

Let's dive in!

As always, thanks for supporting us on your favorite platform:

• 🦋 Bluesky
• ✖️ X / Twitter
• 👔 LinkedIn
• 👽 Reddit

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People always ask how I keep up to date, it's This Week In React.

Jack HerringtonPrincipal Engineer - Youtuber

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⚛️ React

Panda CSS 2.0 - Same styling API, a new engine underneath

This new major version of the type-safe, build-time CSS-in-JS library is the biggest update since launch. Here’s what you need to know:

• The CSS authoring experience doesn't change much.
• The compiler has been rewritten in Rust on top of Oxc.
• DX and builds get dramatically faster, and output better CSS.
• With source transforms, Panda integrates with the bundler so that css(), style props, recipes and patterns are compiled to plain class strings at build time. The styling runtime disappears from your bundle, not just the style-insertion logic.
• You get many new features to play with: a typography preset, publishing your Panda design system and visualize it in Studio, new CSS functions, a better CLI, an official ESLint plugin, and more

Vinext 1.0 - Next.js applications, powered by Vite

Cloudflare's Vite-based reimplementation of Next.js goes stable, supports both App and Pages Router and claims 99%+ compatibility with the Next.js test suite (minus Cache Components). They also have a different opinion of how ISR should work.

What started as a one-off slopfork experiment is now becoming an AI-driven software factory able to keep up with new features landing in the official Next.js implementation. Interesting time!

• 💸 PostHog - I wrote a 70x faster SQL parser while barely looking at the code
• 🔐 Next.js September Security - 16.3.8 and 15.5.27 - New security releases, covering 1 critical, 2 high, 5 medium vulnerabilities.
• 🗓️ React Summit US - 🇺🇸 New York – Nov 17 & 20. Join the creator of React Query, the Executive Director of the React Foundation, and other amazing speakers to dive into the React ecosystem. Save 10% on your ticket with code “TWIR”.
• 📜 GitHub - Improving site performance by shipping more CSS - The multi-year story of an incremental migration from styled-components to CSS modules.
• 📜 Rebuilding React Router's Global Hooks in Next.js - Explains how Next.js and React Router chose to manage state differently. Next.js has no useNavigation() or useBlocker() but you can rebuild them with a Context provider.
• 📜 Props Are Not a Design System - Style props and Tailwind class walls are just inline styles in disguise. Use named variants and modifiers instead.
• 📜 How we made claude.ai 3x faster in two weeks - Practical AI-driven perf work on a real React codebase. For example, their client-side app now renders a static composer so users can type before React even initializes. React commit counts, among many other metrics, serve as deterministic benchmarks for agents.
• 📜 AI, Open Source, and the Long Road to TanStack Charts - Recap of an X Space with Tanner Linsley. Not directly actionable, but interesting to see how he built a new charting library with AI in less than a week, reusing years of experience with Chart.js, react-charts, and Observable Plot.
• 📜 How to Sync a Design System with Claude Design
• 📦 Preact 11.0 - ESM-only, TS 5.1+, Hydration 2.0 with streaming SSR, refs as props, Object.is hook deps, React compat improvements - The first major in 6+ years, shipping necessary breaking changes to move the project forward.
• 📦 React Resizable Panels 4.14 - Grid layout components
• 📦 Redux Toolkit 2.13 - TypeScript 7 support, long list of bug fixes, new unified docs site
• 📦 Oxlint 1.86 - only-export-components now supports compound component, 2 React Compiler fixes
• 🎥 James Quick - Vinext 1.0 - A New Alternative to Next.js

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My favorite resource for keeping up with the React community!

Evan BaconEngineering Manager - Expo

💸 Sponsor

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Performance is at the core of what we build. We work deep in the stack, from JSI and C++ to Swift, Kotlin and React Native’s New Architecture. We bring that expertise to companies too. At Discord we helped tackle performance bottlenecks in its New Architecture migration. Among other improvements, we reduced the Android app’s crash rate by 36% and jank frame rate by 26%, bringing jank back to regular levels.

Want to see how? Read the technical deep dive on our blog and learn more about what we do.

📱 React-Native

• 💸 DeployPulse - Hosted OTA updates for React Native. A drop-in replacement for CodePush and EAS Update.
• 📖 React Native docs - fontVariationSettings - Variable font support - RN 0.88 will support configuring variation axes of a variable font.
• 📜 React Native Modules Cannot Use Android's Activity Result API - Modules load after the Activity starts, so the modern API was unusable from native code. Fix is coming in RN 0.89. No manual setup of MainActivity steps needed.
• 📜 Shipping super-calendar - A story about building a performant solution for RN and web. Virtualized rendering of visible dates only, and Reanimated shared values to skip re-renders.
• 📜 5 react-native-enriched-html Use Cases You Might Not Know About - More than a rich text editor: text processing like the emoji picker runs fully native, avoiding JS-side FPS drops on low-end devices.
• 📜 Agentic CI for Expo apps with TesterArmy - Code output outpaced review capacity, so merges ship with low confidence. Testing like a real user using agents restores it.
• 💸 Maestro MCP - A practical guide to mobile UI testing with coding agents
• 📦 React Navigation 7.23 - Add tabBarRepeatedPressBehavior - Defines the behavior when pressing an already-focused tab. Can scroll content to top and/or pop nested stack screens.
• 📦 Lynx 4.0 - Foldables, Media Queries, Liquid Glass & Blur, WebView, ReactLynx improvements, Generative UI
• 📦 Lucent - Write native modules in TypeScript, compiled to C++ and called through JSI
• 📦 React Native macO 0.83
• 📦 Appduct - Expose app tools to agents and tests, no debug menus in the binary
• 📦 Nitro SQLite 10 - Independent database handles, reusable prepared statements, macOS support
• 📦 Legend List 3.6 - Add viewPositionFallback for oversized list items
• 📦 Angular Native - Build native iOS and Android apps with Angular, built and shipped with Expo
• 📦 Nitro RTMP - Live streaming as a VisionCamera 5 output
• 📦 Plain Text 0.9 - Faster, drop-in remplacement for Text component, proper hyphenation, writingDirection
• 📦 Re.Pack 5.4 - Lazy per-platform Rspack builds, unified commands entry point, RN 0.87 support
• 📦 ViroReact 3.0 - visionOS, Web AR, co-location multiplayer, Studio and MCP tooling
• 📦 Skia 2.13 - Legacy architecture support removed, android.surfaceType to select the backing view, SPM support
• 📦 Sentry 8.28 - Native breadcrumb off-switches, PII accessibility identifier opt-out, MetricKit raw payloads
• 📦 Legend List 3.5 - scrollElement to share an ancestor scrollbar on web, less layout work for single-column lists
• 📦 Argent 0.26 - iPhone Duo simulator support, clearer simulator-server exit errors, Xcode Device Hub for booted simulators
• 📦 Agent Device 0.21.15 - iOS 27 SDK and Xcode 27 support, visionOS simulators, richer Android accessibility snapshots

🔀 Other

• 🐦 TC39 meeting live updates - Progress for Composites, Iterator methods, export defer, and more - Among many other interesting JS proposals, my favorite one progressed! Composites are objects compared by value instead of identity, using interning. This is kind-of the “new version” of the former Records & Tuples proposal.
• 👀 WebSkills - A Huawei contributor recently pitched this at a W3C seminar, and W3C could incubate the project for a future standardization. Agent Skills, stored in the browser, running scripts in Web Worker sandboxes. Very early, but this could complete WebMCP and On-Device AI.
• 📜 Optimizing objects with null prototypes - Using null-prototype objects in hot paths can be a perf bottleneck for V8. Matteo works on Node.js WebStream optimisations, and just changing how those objects are created led to significant perf improvements.
• 📜 CSS linked parameters - One SVG, nine posters - Upcoming CSS feature to style an <img> SVG directly from the page CSS. Can be used today as a progressive enhancement.
• 📜 Electron to PWA: There and Back Again - PWA still can't deliver basic desktop app expectations.
• 📦 Vite+ 1.0 - A single vp command to manage your Node.js runtime, package manager, and frontend toolchain
• 📦 upm - A fast, tiny package manager for the npm registry - Written in TypeScript, yet as fast as Rust alternatives.
• 📦 Mock Service Worker 3.0 - Smaller, ESM-only, granular entrypoints, GraphQL subscriptions, Network API, socket-level Node.js interception - There’s also a new package to integrate with React Native.
• 📦 pnpm 12.7 - node shim follows .nvmrc, install --allow-build flag, wait for published packages to become available

🤭 Fun

See ya! 👋