This Week In React #284 : TanStack Start, Compiler, React Router | App.js, Gesture Handler, SPM, Expo | npm, Node.js, Astro

Hi everyone, Kacper and Filip from Software Mansion here.

This week, TanStack Start is once again in the spotlight. The React Compiler in Rust is on its way. React Router and Remix shipped important security patches – update immediately. There's also a fresh batch of releases from TanStack Form, XState Store, shadcn, React Aria, and more.

On the React Native side, this week was dominated by App.js Conf 2026 in Kraków. Gesture Handler 3.0, Swift Package Manager support for React Native, and Legend List 3.0 were among the highlights, alongside Expo announcements like EAS Observe.

Let's go!

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⚛️ React

TanStack Start Gaining Momentum:

• 📜 TanStack Start Adds First-Class Rsbuild Support - TanStack Start now supports Rsbuild / Rspack alongside Vite via a new plugin adapter, covering SSR, streaming, HMR, Server Functions, and RSC.


• 📜 Lovable - Building apps using TanStack Start - The AI App builder is now using TanStack Start with SSR by default for all new projects.


• 📜 The Conductor Rewrite: What They Changed to Make It Fast - Migrating their Tauri desktop app from React Router to TanStack Router significantly reduced re-renders thanks to its built-in structural sharing and stable refs.


• 📜 TanStack Start authentication: A developer's guide for 2026 - Why beforeLoad doesn't protect server functions, the double-guard pattern, sessions, and middleware.

• 💸 SVAR React Gantt – Build project timelines with a pure React API and advanced scheduling (MIT & PRO)
  


• 👀 React Compiler update - The Rust compiler PR to be merged soon - It already produces at 99.9% the same output as the original TS compiler. You can try it already through a local PR checkout. The Oxc team is already working on an integration (PR).


• 📅 Next.js Nights - The Next.js team on tour (9 June SF, 11 June Amsterdam, 18 June London) - They also teased us about an upcoming v16.3 release, including Instant Navigations and new AI-related features.


• 🔐 React Router & Remix v2 - 7 CVEs published - Includes RCE, CSRF, XSS, and DoS vulnerabilities. Update to React Router v7.16.0 / v6.30.4 or Remix v2.17.5.


• 📜 Deprecating a React component using TypeScript Overload - How to ship a breaking component redesign without renaming it with the usage of TS overload, mark the old API as @deprecated, and let consumers opt into the new version by adding a new prop.


• 💸 PostHog - PostHog Code and the self-driving product
  


• 📦 TanStack Form 1.33 - FormGroup API to simplify multi-step forms
  


• 📦 React Hook Form 7.77 - new resetDefaultValues API
  


• 📦 React Email 6.5 - Filter compatibility warnings by client, accessibility improvements
  


• 📦 TypeGPU React - React bindings for TypeGPU - Hooks like useFrame, useUniform, and useRoot to write GPU shaders directly in TypeScript and integrate WebGPU into React components.


• 📦 Lexical 0.45 - New composable DOMImportExtension replacing importDOM, backspace now preserves block type, canUndo/canRedo signals on HistoryExtension.
  


• 📦 React Aria Components 1.18 - Calendar multi-date selection, month/year pickers, new TableFooter and SliderFill components - Checkbox, Radio, and Switch now support description and error message slots.


• 📦 React Spectrum 1.4 - drag & drop in ListView and similar, TableView highlight selection & TableFooter, custom prefixes in ComboBox/TextField, multi-date Calendar selection
  


• 📦 Shadcn UI 4.9 & 4.10 - GitHub registries, npx shadcn eject to extract any component into your codebase
  


• 📦 Next Intl 4.13 - useExtracted function now generates message keys using URL-safe base64
  


• 📦 React Flow 12.11 - new autoPanOnSelection prop
  


• 📦 XState Store 4.0 - createStoreLogic for reusable stores, enq.trigger for chaining events, Standard Schema support, store.can for event checking.
  


• 📦 React Archer 5.0 - Draw arrows between elements - Add React 19 support
  


• 📦 ESLint Plugin React ”You Might Not Need An Effect” 1.0
  


• 🎥 Jack Herrington - All 17 TanStack Projects In ONE App!
  


• 🎙️ Señors at Scale - Redux at Scale with Mark Erikson
  

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📱 React-Native

Highlights from App.js Conf 2026

Last week, the community gathered at the App.js Conf happening in Kraków. We're highlighting three announcements here, since many of the others shipped over the past month and were demoed again on stage. Make sure to catch the rest of the talks through the live stream recordings (Day 1, Day 2).

React Native Gesture Handler 3.0

Major release rebuilt for the New Architecture, dropping Old Architecture support, introducing a new hook-based API which is React Compiler friendly, a new Touchable component with built-in animations and deeper Reanimated integration.

Swift Package Manager support for React Native

Meta + Expo previewed npx react-native spm, which scaffolds SPM config to replace CocoaPods: generates a committable Xcode project, runs codegen, caches XCFrameworks globally. CocoaPods trunk goes read-only Dec 2. Both Cocoapods and SPM work in parallel during the transition.

EAS Observe

New Expo production performance monitoring service that tracks real-world startup times, render performance, and bundle load times across devices, with release comparison and per-session investigation. Currently in Private Preview, free up to 10K MAU for at least three months.

• 💸 Maestro MCP - Let your AI agent write and run mobile UI tests for you
  


• 🐦 N-API v10 support landed in Hermes trunk - native Node-API addons can now run on Hermes without modification. Still experimental.
  


• 🗓️ Chain React - 🇺🇸 Portland - 30-31 July. The US React Native conference is back! Grab your tickets now and get a 15% discount with code "TWIR"!


• 📜 Things I Learned While Building Expo - Evan Bacon is leaving Expo after 9 years. He wrote what he learned on dogfooding, listening user feedback, building developer trust through rough patches, and why data beats vibes when you're building developer tools.


• 📜 Expo Router v56: Decoupling from React Navigation - Covers the decision to fork React Navigation internals for full architectural control, codemod-assisted migration, streaming SSR with generateMetadata, and new Android toolbar API and Native Tabs customization.


• 📜 Native code in Expo SDK 56: inline modules and type generation - How inline modules let you write Swift and Kotlin files directly alongside your app code, and how expo-type-information automatically generates matching TypeScript interfaces from them.


• 📦 React Native Runtimes - Run RN Components and business logic in isolated Hermes runtimes - This Margelo/Callstack library permits rendering React components on separate JS Runtimes, and share state across them.


• 📦 Expo Desktop - build macOS and Windows desktop app with Expo - Unofficial announcement coming from community.


• 📦 React Native Doctor - New open-source CLI that scans your React Native app for performance and security bugs and fixes them with AI agents


• 📦 TanStack AI 0.23 - React Native support - Chat clients and framework hooks now run in React Native via a new fetcher option.


• 📦 Keyframer.dev - Visual Animation Editor for React Native - Outputs production-ready Reanimated v4 code - drag keyframes on a timeline, or type a prompt and get a useAnimatedScene hook you can paste directly into your project.


• 📦 Legend List 3.0 - Web support added, scroll jump prevention is now core behavior, and maintainVisibleContentPosition is now opt-in and disabled by default.
  


• 📦 Rozenite 1.11 - Network activity timeline & export, performance startup insights, waterfall view, navigation dispatch origin tracking
  


• 📦 @swmansion/react-native-bottom-sheet - Native bottom-sheet components, inline and modal, with content-based sizing and scrollable-child handling
  


• 📦 Sentry React Native 8.13 - NavigationContainer wrapper for React Navigation, iOS Swift Package Manager support, Expo Router param extraction, pause/resume app hang tracking
  


• 📦 Argent 0.9 - new screenshot-diff too, configurable release-age-aware update reminders
  


• 📦 Agent Device 0.16 - Maestro YAML replay compatibility, structured MCP command tools, iOS transform gestures, Android ANR recovery
  


• 📦 Uniwind 1.8 - Vite 8 support, uniwind generate-artifacts CLI
  


• 📦 React Native Purchases 10.2 - Ad tracking support
  


• 🎥 Code with Beto - Why AI-Built Apps Feel Cheap (And How to Fix It)
  


• 🎥 Expo - Where is Expo Go?
  

🔀 Other

• 📊 State of CSS 2026 - Survey is now open
  


• 📜 Node.js streams, backpressure, memory leaks - A pragmatic 2-part deep dive to help you reduce the memory footprint of your streams.


• 📜 On Rendering Diffs – Pierre Computer Company - Deep dive into building a zero-blanking diff virtualizer using the "Inverse Sticky Technique", with insights on layout estimation, DOM pooling, memory optimization, and deferred syntax highlighting.


• 📦 Node.js 26.3 - New permission.drop() API, configurable HTTP header validation, Buffer.poolSize bumped to 64 KiB - Improves the security model, letting you start with the permissions you need for initialization, then drop the ones you no longer need at runtime.


• 📦 npm 11.16 - Phase 1 of package.json allowScripts - npm is rolling out supply chain security improvements in 2 phases, catching up with other package managers. v11.16 adds package.allowScripts=[] and warns on unapproved postinstall scripts. v12.0 will block them by default.


• 📦 Aube 1.17 - Rust-based package manager - Staged publish trust, hoisting limits, remote tarball integrity fixes, and OTP support for dist-tag writes
  


• 📦 pnpm 11.5 - hoistingLimits setting, interactive prompt library, detect staged publishing trust downgrades
  


• 📦 Astro 6.4 - Pluggable markdown processor, Rust-based Markdown processor for faster builds, and Cloudflare helpers for advanced routing.
  


• 📦 Yarn 4.16 - New stage command for staged publishing, editor SDK support for oxc
  

🤭 Fun

See ya! 👋