This Week In React #288 : Next.js, React Compiler, use(), Astryx | Expo, VisionCamera, Windows, Rollipop, LegendList | Node.js, pnpm, TS, Prettier

#react #reactnative

Hi everyone, Seb and Jan here 👋!

This week, the Next.js 16.3 preview makes the headlines, while the React Compiler remains a hot topic.

On the React Native side, Expo unexpectedly shipped a new SDK.

Let's dive in!

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⚛️ React

Next.js 16.3 Preview - Instant Navigations

Next.js 16.3 is now in preview and will be stabilized in the coming weeks. This sneak peek focuses on a new opt-in feature called Instant Navigations, improving on top of Cache Components. This addresses the loudest criticism of the App Router: server-driven navigations feel like clicking a website, not an app.

With this new feature, you will have to make a very explicit choice whenever you await some data on the server, nicely presented in an Instant Insights dev panel to surface slow navigations:

Stream with <Suspense>
Cache with ’use cache’
Block with export const instant = false;

There’s more:

Playwright instant() test helper - Assert what must be instantly visible after a link click.
Partial Prefetching - Instead of prefetching a page per link in the viewport, Next.js will now prefetch a reusable shell per route. You can still prefetch links more aggressively (opt-in).

Also related:

🦋 Dan Abramov joined the Next.js team at Vercel, part-time
📜 Next.js 16.3: AI Improvements - Bundled docs, first-party skills, Agent Browser with React introspection, actionable errors, improved MCP server, and docs as Markdown.
📜 Turbopack: What's New in Next.js 16.3 - Reducing dev server memory by up to 90%, up to 5.5x faster rebuilds with persistent cache, experimental React Compiler in Rust, import.meta.glob API, faster HMR and dev startup.

🗓️ React Summit US - 🇺🇸 New York - 17 & 20 Nov. Call for Papers is open until July 9! Don't miss your chance to share your React stories on stage. Get a 10% discount with code "TWIR".
👀 React Docs - use() API Reference - This React API docs page has been entirely rewritten, also explaining important concepts such as how Promises must be cached on the client.
👀 ESLint Plugin React - ESLint v10 compatibility progress - React users of this ESLint plugin have been stuck on ESLint v9 for a while. Thankfully, v10 support has just been merged into the Import plugin, which should also unlock the React plugin compatibility.
👀 Vercel and Shopify are rebuilding Hydrogen - Vercel is helping Shopify improve its proprietary Hydrogen e-commerce framework. Initially based on React/Remix, the new version should be more portable, supporting Svelte, Nuxt, Next.js, and various server runtimes.
📜 Rolldown Pulls Rust React Compiler Integration After Binary Size Increase - Nicely summarize the tradeoffs of integrating Rust extensions in frontend tools, and whether it’s a good idea for a framework-agnostic tool to have a first-class integration with React. Oxc blocked the integration until it’s slimmed down (in progress), while Rspack chose to ship the Compiler now and optimize incrementally.
📜 React Compiler Is A Retrofit - Argues that, unlike Solid/Svelte, the React Compiler optimizes a runtime model that was not initially designed around a compiler. It can increase bundle size and make the memoization contract of your APIs less explicit. It is safer to use it as a linter rather than a compiler.
📜 Different hydration and rendering strategies - Explains how much JS runs between "looks ready" and "actually works", across every rendering strategy, including non-React ones.
📜 React Testing Questions That Trip Up Engineers - Covering the role of act(), testing implementation details, overmocking, and challenges like testing IntersectionObserver or drag-and-drop.
📜 Open a Modal Dialog in React with the Invoker Commands API - For simple modal dialogs, modern browsers support opening/closing of a <dialog> with a declarative HTML API, no need for useState() nor any JS.
📦 Astryx - Meta’s open-source design system, built on React and StyleX - Meta released an OSS beta version of their design system, built over 8 years and powering 13000+ internal apps, using StyleX atomic CSS-in-JS library. It’s not a headless lib, but highly themable with design tokens and the ability to eject the components to customize them entirely.
📦 Rspack 2.1 - React Compiler in Rust, TanStack Start support, perf improvements, TypeScript 7, import.meta.glob(), and more - Rspack now has a first-class integration with the React Compiler through SWC, reporting it being 7-13x faster than the Babel version. Also, TanStack Start now supports Rsbuild 2.1 through a plugin.
📦 shadcn/ui - Chat interface components, @shadcn/react - This Chat UI update also takes the opportunity to introduce a new package for unstyled, headless React components. For now, there’s only a single <MessageScroller> primitive, but more could come later?
📦 Storybook for TanStack React - A dedicated Storybook framework for TanStack-powered React apps. This provides first-class, type-safe support for TanStack Router, Start, and Query.
📦 Takumi 2.0 RC - Render JSX to images with a single Rust binary - A quite compelling alternative to Satori.
📦 Vinext 0.2 - Revamped init command, prerender, image optimizations, fixes - Cloudflare’s fork of Next.js has been under active development since its initial announcement.
📦 React-Router 8.1 - Agent Skills Installation, Observability Metadata
📦 nuqs 2.9 - Support for React-Router v8, add history to adapters defaultOptions
📦 Frond - Effect-powered frontend runtime for React and MobX-facing application state
📦 RedwoodSDK 1.5 - Vite 8 support
🎥 The Build Log S1E02 - Tanner Linsley Built TanStack to Outlive Him

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📱 React-Native

Expo SDK 57

It feels like Expo SDK 56 just got released, and we’re already on SDK 57, even skipping the beta phase!?

Since RN 0.86 got released with no breaking changes, the Expo team decided to cut the new release sooner than usual. It’s a test of a new release cadence that will follow RN releases more closely. React Native’s move towards stability should make it easier to offer the latest changes almost immediately. Why not do it as a part of the SDK 56 update, then? There are still many changes, and it’s better to make the upgrade intentional to avoid unexpected errors.

RN 0.86 features are now available in Expo: first-class edge-to-edge support on Android, light/dark mode emulation in React Native DevTools, and rendering, layout, and animation fixes. Expo 57 also comes with a list of various Expo-related improvements.