Back after a little break to cover news from the last two weeks. A lot is going on, apparently not everyone is on holiday because we still have many interesting releases, including many RCs from upcoming major versions.
The native React Compiler rollout continues. React v19.3 seems around the corner. Plenty of TanStack Router/Start and Next.js content.
React Native 0.87 is now out, paving the way for v1.0.
ποΈ Weβll be taking another break next week. See you in September. π
True story. Dan Mindru got a GitHub notification at the dentist, skimmed a green PR he hadn't written, and hit merge before his name was called. That was one of 57 bugs in his backlog. He's down to 1 now, and his system sorts every production bug into three tiers: π Friendly: the null check, the off-by-one, the layout that breaks on mobile. The PR is waiting when you wake up. π€ Grumpy: stale state after a websocket reconnect, optimistic UI that never rolls back. Seer can root-cause these, but it can't run your tests. Something else has to. π€ Punk: five-year-old prod data, one customer's flag combo. Still yours, sorry.
βOxlint 1.79 just added support. The new oxc-transform-react package also unlocks automatic memoization and will soon be supported in @vitejs/plugin-react (PR already merged). Along the way, they made many improvements to performance and behavior over the original Rust port and even found bugs in the Babel version.
βBiome 2.5.8 is out with a new useReactCompiler nursery/experimental rule, although itβs an initial version and thereβs remaining work to be done such as splitting the rule into many smaller ones.
π TanStack Router reimplemented - Prominent Node.js contributor Yagiz Nizipli reimplemented TanStack Router APIs, claiming a drop-in replacement up to 19x faster. Tanner Linsley answers.
π¬ Next.js team - Ask us anything on Reddit and Ask us anything on X- Apart from the many Next.js-related discussions, happy to hear that Fragment refs and ViewTransition will be stable in React 19.3! Also gives a preview of upcoming features such as granular prerendering and new data fetching primitives.
ποΈ React Summit US - πΊπΈ New York - 17 & 20 Nov. Incredible lineup announced featuring Kent C. Dodds, Shaundai Person, Ken Wheeler, Tanner Linsley, and Seth Webster! Get a 10% discount with code "TWIR".
π Impersonating the DOM - A quite interesting lib design technique used by React Aria. createPortal(children, fakeDocument) lets you eavesdrop on the reconciler operations and get access to the rendered children. This pattern lets you do various things, such as hoisting/deduplicating SVG .
π How Lovable.dev moved from Next.js to TanStack Start - Lovable builds and hosts primarily TanStack Start apps, so they decided to adopt the framework for their flagship app to dogfood their own platform and turn it into a typical Lovable app. This describes the incremental migration approach: making the code framework-agnostic, using agents, migrating related routes together, and ensuring both frameworks can run simultaneously. The migration brought better DX/AX and simpler abstractions, but TanStack Start requires more bundler customization.
π Making Navigations Instant in v0 - Next.js 16.3 now supports pre-rendering dynamic content at runtime, making navigation feel instantaneous. Assert this behavior with a new Playwright instant() helper, and let your AI agents fix the failing tests with the provided skill.
π Reliable Query Prefetching with TanStack Router - Reliable prefetching requires using the same query options in the route loader prefetches and component queries, which may diverge at scale. Put query options in Route Context to keep them in sync.
π Inside a TanStack Router Navigation - Explains the lifecycle of a navigation and how edge cases are handled, such as using a transaction and private lane system to handle race conditions.
π Building App-like Experiences with Next.js 16.3 - A nice overview of all the cutting-edge Next.js features useful to build modern web apps, illustrated through 4 open source app demos.
π Coordinating Optimistic Updates in Next.js - Use useActionState and useOptimistic to coordinate overlapping transitions with an Action queue, a reducer, and optimistic state with automatic rollbacks. Not so easy to wire, but this pattern can be learned once and applied in many places.
π Using next/root-params in Next.js 16.3 - A game-changer for next-intl, that can now read a [locale] param of a root layout in all Server Components.
Carl Ross (OpenAI) and Nick Miller (Cursor) have recently joined the lineup, alongside other top AI engineers from Google, Meta, Amazon, Expo and other tech giants.
Agenda is now almost full with talks covering 4 main angles:
Vibe Coding
Agentic Engineering Fundamentals
Orchestration & Multi-Agent Systems
Adoption & Case Studies
The last few spots are still available for the free workshop hosted by Amazon on September 16: Build Your Own Software (re)Factory. First come, first served! Book your spot at agent.sh/workshop.β
Join Agent Conf in Warsaw on September 17β18 to get better at coding with AI agents.
Like clockwork, React Native 0.87 is out! It's the biggest step towards RN 1.0 in a long time, coming with intentional breaking changes, so it deserves more than a routine upgrade note.
Strict TypeScript API by default: Types are generated automatically from source and scoped to the package's root, so internal file changes are no longer breaking changes. Dedicated *Instance types (e.g. ViewInstance, TextInputInstance) improve ref typing of built-in components, and doc comments now flow straight into your IDE. Alex Hunt goes into detail about the work that went into this: compatibility fixes for Tailwind, Uniwind, and Expo Web, plus an upstream TypeScript fix for hidden Libraries/ subpaths.
Faster, leaner Metro: Source map generation is now 2x faster and uses half of the memory. Support for TypeScript and ESM config files. βExperimental Swift Package Manager support for iOS: Opt-in and additive: Xcode is enough β no Ruby, no Bundler, no CocoaPods. CocoaPods remains the default path.
Android Gradle Plugin (AGP) v9: First RN release to support AGP 9, with recommended opt-outs for built-in Kotlin and the new DSL until AGP 10.x.
API surface cleanup: Many deprecated APIs have been removed, including flagship ones like InteractionManager. New APIs are marked as deprecated and scheduled to be removed later. AbortController is now complete and backgroundImage: linear-gradient/radial-gradient is now stable.
New requirements: The minimum toolchain requirements is now Node.js 22, AGP 9, and Kotlin 2.0+.
ποΈ React Native Connection - π«π· Paris - 24 Sept. Deep dive into mobile development with top-tier experts from Expo, Software Mansion and Callstack. Regular ticket window closing August 31. Save 15% on your ticket with code "TWIR".
π The Memory Hermes Can't See: Stale Shadow Nodes in React Native - Recent Hermes V1 memory regression triggered additional experiments that surfaced a fascinating finding about the Shadow Tree. Unmounting views causes the React component and the objects attached to it to still exist in memory, which can only be cleaned up by GC run.
π How we raised mobile end-to-end test stability to 98% - Shopify stopped patching their Appium E2E suite to fix flaky tests with an opinionated wrapper. They moved away from testing implementation details with TestIDs to using computer vision.
ποΈ RNR 369 - AppRegistry Explained - Breaks down RNβs AppRegistry. Whatβs under the hood. From Expo and app entry points to brownfield apps and more.
ποΈ RNR 370 - CopilotKit with Mike Ryan - Bringing AI agents to RN apps. Breaks down of AG-UI, generative UI, shared state, and the guardrails needed for trustworthy experiences.
β
π Other
π CSS: the bomb inside your inbox - Novel hacking techniques showing how CSS sanitizers in Gmail/Outlook/Fastmail can be worked around to steal tokens, hijack clicks, or keylog passwords.
π Read Online Hi everyone, Kasia and Kuba from Software Mansion here. This week, Next.js 16.3 officially shipped, bringing Instant Navigations to the App Router and cutting dev server RAM usage by up to 90%. On the React Native side, a new, faster PlainText component and a deep dive into Vision Camera v5. Across the broader dev ecosystem, GitHub stacked PRs finally entered public preview with native base retargeting and a gh-stack CLI. Let's dive in! ποΈFYI: weβre taking a break next week; see...
π Read Online Hi everyone, Seb and Jan here π! This week we have an interesting React challenger, keeping its mental model but compiled ahead of time. Also various major announcements from the TanStack side. On the mobile side, we have interesting RN 0.87 PRs to look at, discussions around workers / worklets, a WebGPU/Skia integration, and React Navigation 8 / Screens 5 progress. Last week, many proposals progressed during a TC39 meeting. npm is going to scan for malware at publish time. Core...
π Read Online Hi everyone, Seb and Jan here π! This week we have React and Next.js security patches. React Aria becomes first-class in shadcn. A benchmark grades coding agents at real React tasks. The rise of TSRX and its upcoming framework. On the mobile side, Swift Package Manager support is finally coming. A TC39 meeting is in progress; we'll share the proposal updates next week. Oxlint type-aware linting is ready for prime-time. Meanwhile, Yuku explains how it outperforms Oxc at parsing...
