This Week In React #279 : Compiler, TSRX, StyleX, XState, Hook Form | SPM, SimCam, Enriched Markdown, Agent Device | pnpm, Aube, Fresh, Node.js

#react #reactnative

Hi everyone, Konrad and Kacper from Software Mansion here! 👋

A quiet week — no big headlines — but still a couple of solid articles and releases in the React ecosystem.

On the React side, the WIP React Compiler in Rust is being tested at Meta. We also have a 18-month retrospective on the React Compiler, a deep dive into how React streams UI, and a step-by-step guide for migrating from Radix UI to Base UI. There's also a fresh batch of releases, including React Hook Form, Chakra UI, Mantine 9.1, and TanStack Query.

On the React Native front, an RFC has landed proposing Swift Package Manager support to replace CocoaPods, and React Navigation v8 will gain a retain API to keep screens mounted after going back. Don't miss the blog on making pure JSI code faster.

Let's dive in!

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⚛️ React

💸 Crowdin - AI localization platform that automates your React app translations from code to deployment.
👀 WIP port of React Compiler to Rust - Confirmed being internally tested at Meta.
📜 The React Compiler at Eighteen Months: The Arc, the Debates, and What's Next - An overview of what happened since React Compiler was announced and predictions for the future.
📜 How React streams UI out of order and still manages to keep order - Deep dive into Suspense boundaries and DOM staging.
📜 Accessibility in React: Common Mistakes and How to Fix Them - HTML elements, document structure, interactive elements labeling, connecting errors to labels, focus management, dynamic updates, ARIA.
📜 Migrating from Radix UI to Base UI: Step-by-Step Guide - Covers the main API differences: asChild becomes a render prop, data-[state=*] attributes are replaced by ARIA attributes, and component-specific changes like Select now take an items array.
📜 Why TSRX isn't just your Favorite Templating Language - TSRX is an alternative to JSX. The article states that TSRX’s mechanics (static analyzability, stateful templates, hooks in conditionals) matter more than syntax.
💸 Product for Engineers - The golden rules of agent-first product engineering
📦 React Hook Form 7.74 - setValues update multiple fields at once
📦 React Tooltip 6.0 - portalRoot and autoClose props, React 19 support, removed HTML string API
📦 shadcn CLI 4.5 - Add --pointer option to cli - Re-enables cursor: pointer on buttons.
📦 XState 5.31 - Add mapState(snapshot, mapper) and maxIterations option
📦 StyleX 0.18 - New sx={} JSX prop, stylex.env compile-time constants, create-stylex-app CLI, DevTools extension, Bun support
📦 Chakra UI 3.35 - new release for: react, charts, cli, panda-presets and codemod packages - This release adds a Splitter component, React 19 support, and new CLI commands for docs/props.
📦 @hono/inertia - Inertia.js on Hono, render React from your routes - Skips the REST endpoints, client side router and the data fetching layer entirely with this new end-to-end type safe middleware.
📦 Mantine 9.1 - Added/modified: deduplicateInlineStyles, use-mask, MaskInput, Treemap, TimePicker, Heatmap, MonthPicker, YearPicker, use-roving-index, Tree, Slider, WeekView
📦 TanStack Query 5.100 - Added retryOnMount callback; internal Svelte test cleanup
🎥 Josef Bender - Avoid These 3 Mistakes in TanStack Start
🎥 Jack Herrington - Partial Page Caching Using React Server Components

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📱 React-Native

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💬 RFC: Swift Package Manager support in React Native - Plan to replace CocoaPods with SPM on iOS, as CocoaPods has been in maintenance mode for a while.
👀 React Navigation PR - Add support for retaining screens in stack - A new navigation.retain(true) API will keep a screen mounted after going back, similar to React's <Activity>. JS stack only for now, but Native Stack support will come with RNScreens 5.
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📜 How to Make Pure JSI Code Faster in React Native - HostFunction is about 5x faster than HostObject, prefer stack buffers when size is known, avoid unnecessary temporary allocations, reduce JS ↔ C++ crossings.
📜 QR and Barcode Scanning in React Native with VisionCamera V5 - Overview of VisionCamera APIs for QR scanning with ranging purposes & levels of complexity.
📜 Integrating Deferred Deep Linking in React Native Apps - React Native Detour SDK walkthrough with Expo Router.
📜 When to Use Apple Foundation Models on Mobile - Hybrid approach where local models handle latency-sensitive tasks and cloud models handle complex reasoning. Use local first and escalate to cloud when needed.
📦 SimCam - Camera Testing for the iOS Simulator
📦 Quick Crypto 1.1 - simdutf for faster string encoding/decoding, Buffer semantics now match Node.js semantics, OpenSSL-Universal CocoaPods dep
📦 Enriched Markdown 0.5 - Support macOS, web, EnrichedMarkdownTextInput, spoiler elements, auto-link detection, VoiceOver/TalkBack improvements
📦 Agent Device 0.13 - React DevTools passthrough, parametrise .ad replay scripts
📦 iOS Simulator MCP 1.6 - Added ui_find_element tool, launch_app env variable and record_video UDID support
📦 Google Maps RN Navigation SDK 0.15 - Breaking changes to continueToNextDestination and mapStyle; various iOS/Android crash fixes
📦 Nitro MLX 0.5 - Expo 55 support, added Embeddings module, ChatSession API, and streaming downloads
📦 Expo Paste Input 0.2 - Animated GIF stickers, preserve animation instead of converting to static images
📦 Jail Monkey 3.0 - New Architecture support, added iOS/Android mock location detection - Detect jailbroken/rooted device, mocked locations, and on Android apps running from external storage.
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🔀 Other

👀 Node.js PR - Release v26.0 - The release slipped from yesterday to next week. It upgrades the fetch() client and unlocks new exciting APIs such as Temporal and Map.getOrInsert().
📜 Scroll-Driven Animations - Another great interactive article from Josh Comeau, explaining how you can now map a CSS keyframe to a scroll distance instead of a duration.
📜 Compositing & Blending - How the browser decides the final color of every pixel when stacking multiple elements and how it is applied in the real world.
📜 The Web Is Fun Again: First Experiments with HTML in Canvas - Showcases a new API, with its limitations and interesting ways to use it.
📜 New to the web platform in April - contrast-color(), animation-range, and Math.sumPrecise became Baseline Newly Available, while Firefox and Chrome added various new APIs.
📦 pnpm 11.0 - SQLite-backed store, supply-chain protection on by default, native publishing, ESM-only
📦 Aube - Drop-in Node.js package manager that reads existing lockfiles - Claims to be 9.2x faster than pnpm and 2.7x faster than Bun.
📦 Fresh 2.3 - Preact framework - Zero JS by default, View Transitions, and Temporal support
🎙️ Syntax.fm 999 - Writing Maintainable CSS