JavaScript Weekly
Plus the js1024 winner, a train-inspired JavaScript optimization, and Bun 1.4 is still on the way.

#​798 — August 11, 2026

Read on the Web

🏖️ A brief scheduling note: We're taking a summer break next week, so we'll be back in your inbox on August 25. Catch you then!
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Your editor, Peter Cooper

Together with  Render

JavaScript Weekly

Migrating a Large Flow Monorepo to TypeScript — Over several years, Yelp moved 1.4 million lines off Flow, and this writeup is more useful as a guide to running any long migration than as a Flow story. It was a big win on its own terms, with type coverage up from 83% to 96%.

Shawn Walton (Yelp)

💡 If you missed it, Yelp also wrote about its webpack to Rspack migration.

Render Runs JavaScript, Front to Back — Link your repo and Render takes it from there. Wire up your Vite site to your Hono API to your BullMQ job to your distributed agent workflow, all on one platform. Loop in your agent with official Render /plugins for Codex and Claude Code. Start free and scale from there.

Render sponsor

Kitesurf: Cloudflare's Agent-First Browser in V8 Isolates — A browser engine that runs on Workers with one isolate per page. Aimed at agents rather than humans, it uses 3-7x less CPU and memory than Chromium, at the cost of being slower. You can try it out now in beta, and it'll be open sourced in due course.

Martinho, Constant, Figueira, and Duarte (Cloudflare)

IN BRIEF:

RELEASES:

📖  Articles and Videos

How Baseline Can Help You Ship Less JavaScript — A practical audit method for your dependencies. Groups them into clusters (Intl, HTTP, UI primitives, lodash), gives you questions to ask before deleting things, and works through a case where a swap can make your bundle bigger (Day.js → Temporal). A familiar theme developed into a rigorous, reusable audit.

Jad Joubran

Making More npm Packages Work with jsDelivr ESM ModejsDelivr is a popular CDN used to load npm packages into pages without a build step. This is a thorough, technical tour of what happens when converting packages to browser ESM (via its /+esm endpoint) and all the ways CommonJS finds to make that hard.

Martin Kolárik (jsDelivr)

Join Sentry Live: How Etsy Stays Crash-Free — Sentry and Etsy break down how they prep for peak traffic and debug in real time.

Sentry sponsor

Progressive Enhancement Inside of JavaScript — Working on a train, a patchy data connection got Remy to notice users can interact with a page before its JavaScript is ready, with a neat fix being to bind a handler early and replay the intent later.

Remy Sharp

📄 How the Astro Team Built a 'Software Factory' to Slash Its Issue Count – Agent-driven triage took Astro from over 200 open issues to 30. Matthew Phillips

📄 Debugging Stuck Node.js Processes – A trick for catching event loop blockers that never yield. Winona Schroeer-Smith

📺 Stop Reviewing Diffs. Start Reviewing Systems Kent C. Dodds

🛠 Code & Tools

celld: Durable Objects on Your Own S3 Bucket — A self-hosted take on Cloudflare's Workers and Durable Objects from Deno. V8 plus SQLite and Litestream's LTX coordinate through an S3 bucket with no consensus layer. GitHub repo.

Ryan Dahl (Deno)

😅 On self-hosting Durable Objects with workerd, "You beat us to it!" said Durable Objects creator Kenton Varda on Hacker News, later adding "celld is definitely ahead of us here. No doubt about that."

That Slow Tab Isn't the UI. It's the Query — TimescaleDB extends Postgres so queries stay fast at scale, straight from live data. Get $1000 credit to start.

Tiger Data (creators of TimescaleDB) sponsor

hucre 1.0: A Zero-Dependency Spreadsheet Engine — An MIT-licensed, tree-shakeable engine for reading and writing common spreadsheet formats, including support for things like embedded images, hyperlinks, password protection, and pivot tables.

Wind

vlt 1.0: An npm Alternative With CSS-Like Selectors — A drop-in npm alternative with a key draw being vlt query, which lets you use 60+ CSS-like selectors over your dependency graph (of which half are security related). vlt also offers hosted private package registries.

Darcy Clarke

TanStack Table v9: A Faster, More Modular Foundation — The headless table library gets a tree-shakeable architecture, state moves to TanStack Store for fine-grained reactivity, and there are big memory wins for large datasets.

Kevin Van Cott

  • devalue 5.9 – The Svelte project's more powerful JSON.stringify supporting more JS language features.

  • Svelte Select 6.0 – A select/autocomplete/typeahead Svelte component. Now requires Svelte 5.

  • fuzzysort 4.0 – Fast, small fuzzy search library with ranking and custom scoring.

  • GTKX 1.0 – Build native GTK4 desktop apps with React and TypeScript.

  • Belgie 0.40 – Embeds a permissioned Deno runtime in Python.

📰 Classifieds

Which screen is slow, and on which devices? Expo Observe is production performance monitoring for your mobile app.


🤖 Block bots at login without slowing down real users. No CAPTCHAs, zero friction. Try Fingerprint for free.


Merget is Git for AI-written code. It reviews every coding session and catches what your agent missed. Free for teams now: merget.ai.

📢  Elsewhere in the ecosystem

I'm off on vacation at the end of this week, so see you again on August 25! Or in Node Weekly and React Status if you subscribe to those… ;-)

Issue 797 #798