React Skills, json-render, ViewTransition, Base UI, shadcn, Store, Apollo, MDX, GTK | RN Windows/macOS/Harmony, Brownie, Enriched, Navigation, Teleport, Nitro | TC39, Astro, jQuery, Node.js

Agent Skills

A new Anthropic spec is gaining traction in the AI dev community. Skills let agents acquire capabilities on demand via progressive disclosure—lazy-loading only what’s needed to keep context slim. It’s been a hot topic in React this week, with multiple projects shipping open-source skills and tooling:

• Skills.sh, a platform launched by Vercel to discover popular open source skills

• React Best Practices by Vercel for React and Next.js skills. I also liked the related article from one of the authors (Performance Is Not a Technical Problem).

• React Native Best Practices by Callstack, including many React Native optimization skills

• Expo Skills for Expo apps and EAS projects

• Remotion Skills are trending on X, showing that you can vibe code videos with React 🤪

Firefox 147

You might wonder why Firefox is the headline of the React section? It turns out this release is quite important for React developers, unlocking 3 new APIs that are now available in all browsers 🎉:

• View transition types - React is relying on it (document.startViewTransition({update, types})) to conditionally enable its <ViewTransition> component. That component is still canary, but once unflagged, it should now work in all recent browsers!

• CSS anchor positioning - An awesome addition to CSS that should replace the need for JS-based positioning libraries many React apps used for dropdowns and tooltips, such as Tether, Popper.js, Floating UI…

• Navigation API - This completely redefines the APIs used to build client-side routers / SPAs, providing a clean, centralized way to intercept navigation events, instead of using the clunky history API.

• 💸 10 Real-World React App Examples to Inspire Your Next Project

• 👀 React RFC PR - useStore/createStore APIs - A POC of implementing a React Store that is compatible with concurrent rendering, for discussion purposes.

• 👀 Prettier PR - Upgrade MDX parser - Support for MDX v3 is finally coming.

• 🔨 TanStack Builder alpha: A website to let you assemble your own TanStack visually. It looks like a convenient visual wrapper around create-tanstack-app.

• 🗓 React Paris - 🇫🇷 Paris & Online - 26–27 March - React Paris is already 50% sold out - Secure your spot at this premier React event before prices increase by €200 and save an extra 10% with code "TWIR".

• 📜 useOptimistic Won't Save You - An interactive article showing that it’s not so easy to implement optimistic UI correctly, even with the new useOptimistic and useActionState APIs. This requires a good understanding of how React transitions work.

• 📜 Inside Turbopack: Building Faster by Building Less - Deep dive into the new default bundler of Next.js and its fine-grained and automatic incremental caching system.

• 📜 Front-end testing at Preply: shifting left towards component testing - Reorganizing front-end testing at scale by moving toward a Storybook-centric component testing approach.

• 📜 Adapting Library Logic for React Compiler - The author of TanStack Form explains a problem encountered with the React Compiler that was not reported by the ESLint plugin. Using the compiler panicThreshold helped detect this problem more reliably.

• 📜 Node.js - Mitigating Denial-of-Service Vulnerability from Unrecoverable Stack Space Exhaustion for React, Next.js, and APM Users - Node.js servers relying on AsyncLocalStorage (used by React RSC and Next.js) can eventually be crashed with a single request containing a deeply nested JSON payload processed recursively. They mitigated the issue in v24.13, but still recommend removing potential attack vectors from your app.

• 📜 Rebuilding the GitHub pull request experience - This dev explores how GitHub’s PR UI could be much faster, especially for large PRs, and shares lessons learned. His Next.js + React 19 demo shows impressive performance compared to GitHub’s current experience.

• 📜 React Slot/asChild Composition Pattern - The article also highlights how Base UI composition pattern differs from Radix UI.

• 📜 Can You Fetch Data with React Server Actions? - Not recommended, but technically possible, with caveats: no caching, requests are POST-only and generally processed sequentially by frameworks.

• 💸 Make React apps fast where it actually matters. Learn how to diagnose real bottlenecks and fix slow, janky React apps using modern React 19 patterns.

• 📦 json-render - AI-generated UI with guardrails - Vercel introduced a new generative UI library. It lets users generate more complex dashboards, widgets, apps, and data visualizations from prompts, using a React component catalog you provide.

• 📦 TanStack Router 1.152 - Allow custom fetch() implementation for server functions - This is useful for interceptors, auth, retry, testing and more (docs).

• 📦 Base UI 1.1 - New features for Autocomplete, Combobox, Select, Field, various bugfixes - By the way, we recently announced Base UI support in shadcn, and Base UI components are now officially documented.

• 📦 shadcn 3.7 - New npx shadcn registry add command

• 📦 GTKX - Build native GTK4 desktop apps with React and TypeScript

• 📦 Puck 0.21 - Visual editor for React - AI page generation, rich text editing, new Plugin interface

• 📦 Warper - Fast React virtualization library powered by Rust and WebAssembly

• 📦 React Error Boundary 6.1 - Fix error type (Error -> unknown), add getErrorMessage(e) helper

• 📦 Apollo Client 4.1 - Support for @stream directive

• 🎥 Maximilian Schwarzmüller - Is TanStack Start better than Next.js?

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Evan BaconEngineering Manager - Expo

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📱 React-Native

• 💸 Radon PRO – everything you need in one React Native IDE: debugger, element inspector, router integration & more. Try it now for free!

• 📅 React Universe Meetup at Zalando - January 29, Berlin

• 📜 Huawei x Software Mansion: Bringing React Native Support to HarmonyOS NEXT - Software Mansion helps Huawei bring RN support to their OpenHarmony OS (already powering 27 million devices), ensuring their famous libraries are also compatible (Reanimated, Screens, Gesture Handler…)

• 📜 Channel surfing for Expo Updates: How to switch update channels at runtime - A technique to let your app’s user decide which Expo update channel to use on their own. You can limit this feature to your employees, for example.

• 📜 Making AI feel human in a mobile app with Expo, Reanimated, and Skia

• 📦 React Native Windows 0.81 and React Native macOS 0.81 - Out-of-tree platforms are catching up, enabling the New Architecture by default.

• 📦 Brownie - Type-Safe Shared State for React Native Brownfield Apps - Creates a single source of truth that lives on the native side, accessible from both TypeScript and Swift. Support for Kotlin is coming soon.

• 📦 Enriched 0.3 - Rich Text Editor - H1->H6 heading styles, text selection API, custom links detection, and more - See also the newly-released sister project Enriched Markdown that renders Markdown content as native text.

• 📦 React Navigation 8.0 alpha - Native Bottom Tabs by default, improved types, access to parent screen state, pushParams, and more - Note that since this initial alpha release, alpha.1 has been published and includes even more features: automatic deep links, SFSymbols/Material Symbols, improved screen preloading.

• 📦 Screens 4.20 - formSheet dynamic content size, a11y & testing improvements

• 📦 RNSec 1.1 - Path exclusion, incremental scanning, cleaner output, rule ignoring, and more

• 📦 Audio API 0.11 - Recording to file, new Web Audio API nodes, DX improvements

• 📦 Teleport - The missing native portal implementation for React Native

• 📦 Bottom Sheet Stack - Stack manager for Bottom Sheet - Preserves React context, Portal-based API

• 📦 Nitro 0.32 & 0.33 - View recycling, custom UIView subclasses, Performance & DX improvements

• 📦 Expo iCloud Storage - React Native wrapper for iCloud's NSUbiquitousKeyValueStore

• 📦 React Native Testing Library 14.0 beta - React19+, async APIs, new renderer, migration guide available

• 📦 Native Spring Shaders - High-performance native shader effects for React Native and Expo

• 📦 Header Motion - An abstraction for scroll-driven header animations

• 🎥 Callstack - Understanding Threads and Queues in Swift TurboModules

• 🎥 Expo - AI mobile app development with Replit and Expo

• 🎙️ React Universe on Air - Shipping v0 iOS: React Native Without Compromises

🔀 Other

• 📣 The Astro Technology Company joins Cloudflare - Interesting to see another popular framework join a tech giant. It will remain free, open source and MIT-licensed.

• 👀 TC39 - Agenda for the 112th meeting - Currently in progress, some JS proposals already progressed, such as map.getOrInsert() (stage 4) and import.sync() (stage 2).

• 📜 The Curious Case of the Shallow Session SPAs: Alex Russell argues that most SPAs shouldn’t be. Data shows that, on average, users produce a single soft navigation after the initial load, and that the upfront cost we pay is probably not worth it.

• 📜 Stop turning everything into arrays (and do less work instead) - Pragmatic introduction tio iterators.

• 📜 Web dependencies are broken. Can we fix them?

• 📜 JavaScript Frameworks - Heading into 2026

• 📦 Node.js 25.4 - require(esm), compile cache, and various other APIs are now stable

• 📦 jQuery 4.0 - Remove IE11 support and deprecated methods, slimmer

• 🔗 Node.js package examples - The Node.js team created a guide on package shipping patterns and how to handle CJS/ESM.

🤭 Fun

See ya! 👋