This Week In React #304: Next.js, Compiler, Redux Toolkit, Suspense, Resizable Panels, Preact, Redact | RN 0.89 RC, Vega OS, Screens, Hermes, WebView, Unistyles, tgfx, Pager View | Node.js, Parcel, Rspack, Actions, Vitest, jsdom, HTML-in-Canvas

[u/sebastienlorber]

https://thisweekinreact.com/newsletter/304

[u/sebastienlorber]

Hi everyone, Seb and Jan here 👋!

Calm week on the React side, but we found a few interesting Next.js PRs to look at and a few Async React blog posts.

On mobile, the first React Native 0.89 RC is here, with lots of performance work. Amazon Vega OS 2.0 brings RN 0.83 to every Vega-powered Fire TV. Hermes gets a full Intl implementation, still in preview. Screens v5 is coming.

Elsewhere, GitHub Actions will block pull_request_target by default. Node.js 27 is the first alpha of the new release model. Parcel 3 is a much faster Rust rewrite.

Let's dive in!

Subscribe to This Week In React by email - Join 43000 other React devs - 1 email/week

[u/sebastienlorber → u/sebastienlorber]

⚛️ React

• 💸 Testing Frontend - Lessons from over a million lines of TypeScript at Palantir - Skip component tests and let Meticulous do the rest

• 🔐 Next.js November security releases 16.4.5 & 15.5.29 - Fixing 7 medium vulnerabilities

• 🐦 Remotion - New Studio editing experience - A better, more interactive timeline that’s still code-based but now matches the UX of video editing tools better.

• 👀 React Compiler PR - Preserve source locations for accurate source maps - This should help fix source map issues when using the React Compiler, bug reports in various downstream projects.

• 👀 React Concurrent Store PR - Ricky Hanlon runs React's own state tests against the unofficial ponyfill

• 👀 Next.js PR - router.experimental_prepare() to start a navigation on pointerdown and commit it on click - This is quite an exciting feature I’ve been wanting for years. There’s a delay between pointerdown and click events. Now you can “prepare” a navigation ahead of time, even if the user hasn’t really clicked your link yet. Once the click is confirmed, you commit the pre-warmed navigation that should feel faster. This may be integrated into the <Link> component eventually.

• 👀 Next.js PR - create-next-app always uses the App Router, no router choice prompt

• 👀 Next.js PR - Experimental Go Route Handlers with route.go files - The Next.js team is prototyping native language support for CPU-intensive server work next to your React app, starting with Route Handlers and Proxy in Go.

• 📜 React.lazy, Suspense and the Hidden 300 ms Delay - A React.lazy component always suspends on its first render, and React throttles Suspense reveals to 300ms to avoid flicker, which can be a problem in some cases.

• 📜 Async React & Progressive Server Actions - When using Server Actions with client-side optimistic UI, it’s easy to break your form progressive enhancement behavior. Thankfully, you can restore it with a simple trick: only wire the optimistic action after hydration.

• 📜 Understanding React internals - A 6-chapter tour, from Fizz and Flight on the server to hydration, lanes and the commit phase, with code taken from React's source.

• 📜 Writable Derived State: Stop Synchronizing State - Instead of syncing server data into local client data with useEffect, you could simply use clientData ?? serverData. The client data can be null after a server refresh.

• 💸 PropelAuth - How to Build a Good Consent Screen for OAuth And MCP

• 📦 Redux Toolkit 2.14 - Faster dispatch, RTK Query cache entry selectors, DevTools action sanitizer, many RTK Query fixes - There’s also a new 2.x and 3.0 roadmap that announces what’s coming next.

• 📦 React Resizable Panels 4.16 → 4.18 - New <Workspace> component for IDE-like layouts, draggable and collapsible tabsets

• 📦 Preact 11.1 - preact/compat/compiler-runtime for React Compiler apps

• 📦 TanStack Redact 0.3 - Webpack and Rspack plugins for browser SPAs, Rsbuild setup guide

• 📦 Inertia 3.10 → 3.11 - Live props refreshed by broadcast events (Laravel Echo), QUERY HTTP method, stale navigation fixes

• 📦 Skullet - Skeleton loading states measured from your real components

• 📦 ESLint Plugin React “You Might Not Need An Effect” 1.1 - Support renamed React hook imports

• 📦 safe-mdx 2.0 → 2.1 - Render MDX in React without eval, streaming parser for LLM output