Hey guys,
Welcome to another edition of Import React by Cosden Solutions!
Big week. Shopify is walking away from React Native after six years, and the reason isn't that it failed. There's a catch in their benchmark numbers, though, and an Expo founder called it out. Also in this issue: a Chrome feature your users turn on that can unmount your React app, a dropdown that went from 1,256ms to 96ms INP without a library, and a traffic light you should be able to build in 10 minutes (the trap is the cleanup).
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⚡️ The Latest In React
📱 Shopify Is Going Back To Native
Six years after going all-in on React Native, Shopify is rewriting its mobile apps in Swift and Kotlin. Their reasoning: coding agents mean building everything twice doesn't cost twice anymore. The 12-week Shop app rewrite came back with big numbers: Android startup down 50%, iOS down 23%, and crashes down 10x. But not everyone buys the comparison. The r/reactnative thread has the one detail about the old app that changes how those numbers look.
🇩🇪 reactCon, droidCon And swiftCon Are All In Berlin Next Month
If the Shopify news has you rethinking native vs cross-platform, next.app devCon puts both camps under one roof, 7–9 October in Berlin. One ticket gets you into all of it: reactCon, droidCon, swiftCon, flutterCon, agentic codingCon and the techlead Summit, plus keynotes, workshops and the expo. There are team ticket packages too, and bundles with a hotel included if you're travelling in.
🌐 Your React App Can Unmount When A User Turns On Chrome Translate
If you've ever seen a random removeChild error in production and couldn't reproduce it, this might be why. The common fix you'll find online makes the crash go away but leaves the UI broken. This post explains why.
🚦 Can You Build A Traffic Light In 10 Minutes?
The UI is already built. You just write the logic that cycles red → green → yellow forever, each light with its own duration. It sounds trivial until you get to the useEffect cleanup. One of 5 fundamentals problems someone shared on r/reactjs to shake off interview rust.
⚡ From 1,256ms To 96ms: Fixing INP In A Massive React Dropdown
A MultiSelect with about 1,200 options was freezing the main thread every time it opened. No library needed, just a 90-line hook that leans on one thing most dropdown lists have in common.
🧱 Over-Abstracted React Costs 30% More To Maintain With AI Agents
The author built the same app at different levels of abstraction, then measured what it cost an agent to edit each one. The over-engineered version burned 30% more time and money. Plus 6 patterns you'll see in most React codebases that you can probably just inline.
✨ CSS Finally Has Native Squircles
Josh Comeau's playground for the new corner-shape property: squircles, bevels, notches and scoops, with borders and shadows that follow the shape. It's Chromium-only for now, but it's purely cosmetic, so you can ship it today. Go play with it.
Quick Links
The React Compiler Is Now Fully Rust — One team moved a 1,000+ file app to oxc's port of the compiler, and the compile step dropped from 14.3s to 0.81s. It also handles patterns the Babel version skips, and the Vite config to switch is at the bottom.
How The Next.js Team Closed 1,500 GitHub Issues In A Month — Yes, agents were involved.
What It Actually Took To Move Discord To RN's New Architecture — Only 14% of the tickets were the migration itself. The rest was a long tail of broken assumptions.
Tailwind Labs Is Joining Shopify — Same team, still MIT-licensed. Tailwind isn't going anywhere.
Attackers Are Mass-Scanning For Exposed Vite Dev Servers — They're exploiting a
server.fs.denybypass to pull.envfiles. It's patched in Vite 7.3.2 and 8.0.5, so update, and double-check your dev server isn't open to the internet.You Don't Need A Mac To Build iOS Apps Anymore — Expo's EAS now runs iOS simulators in the cloud, so you can test from any OS or a browser.
Modern Web Types — TypeScript only types DOM APIs that ship in 2+ browser engines. This drop-in replacement lowers that to 1, so you can use newer APIs without
@ts-ignore.
🧠 AI & General Programming
🧩 Same Async/Await Code, Four Different Results
A quiz on how JavaScript, Rust, Python and Swift run the same async snippet differently. Take the quiz before you read the answers.
🔐 Escaping The OpenAI Codex Sandbox, Twice
One escape pulled a trusted token out of a shared JavaScript heap to reach the unsandboxed parent process. Both were fixed within eight days. The lesson: keep real credentials outside whatever you're sandboxing.
🤖 1,393 Agents Refactored A Million-Line Codebase
It took about 19 hours and $19,300, and cut 34.4% of the source. Tests passed. Human reviewers still found removed public APIs.
🧹 AI-Written Code Is About Twice As Sloppy As Human Code
Correct doesn't mean clean, and on multi-round tasks the strict pass rate hit 0% as bad decisions piled up.
🤔 Why Aren't Better Models Making Us Faster?
Armin Ronacher on why models this good still aren't making us more productive.
🔁 Programmers Dislike reducemap and filter sail through code review; reduce gets flagged. A few theories on why.
📦 Also shipped: pnpm 12.4, which now installs Rust crates and Python packages next to your npm deps · React Router 8.4, with state split into 4 contexts so useLocation() re-renders less.
✅ Reaching Developers Doesn't Require Tracking Them
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💭 One Thing I Keep Thinking About
I don't think the Shopify post is really about React Native. The interesting bit is the claim that writing code twice doesn't cost twice anymore.
If that's true, it doesn't stop at mobile. A lot of what we build in React exists to avoid duplication: shared components, hooks, abstraction layers. But look at the abstraction piece above. The same agents that make duplication cheap also pay a 30% tax on every layer they have to wade through.
What doesn't get cheaper is living with two codebases: reviewing them, debugging them, keeping them in sync. Same story with the Hermes refactor: tests passed, and humans still caught what broke. I'd want to see Shopify's numbers in two years.
See you next week,
Darius