fidzu : javascript

#​752 - September 12, 2025

Read on the Web

If you have any interest in music and being able to render music or generate music with JavaScript, be sure to check out the very end of this issue where we've dedicated an entire section to the topic :-)
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Your editor, Peter Cooper

JavaScript Weekly

How to Keep package.json Under Control - Staring at a 863 megabyte node_modules folder for Val Town's React app, Tom got to thinking about 'dependency hygiene' and some good ways to keep things under control. Good tips and tool recommendations here.

Tom MacWright

Behind the Scenes of bun install - Talk about an epic post. This is no mere explanation of how Bun quickly and efficiently installs packages - but a tour of package installation more generally, the underlying technicalities that make package installation tricky universally, and how Bun has tackled the problem.

Lydia Hallie (Bun)

Stop Reinventing Forms. Use SurveyJS Instead - SurveyJS UI components let you build JSON-driven forms, render them in React, Angular, Vue 3, or plain JS, and store results in your own DB. Open-source, extensible, no vendor lock-in - save months of development and stay in control of your data.

SurveyJS sponsor

A Major Supply Chain Attack Hit the npm Ecosystem - Socket warned us about a phishing campaign targeting npm package publishers which, sadly, bore fruit earlier this week when a variety of popular packages became compromised (like Chalk, DuckDB's distribution for Node.js, debug, and many others).

Gooding, Brown, et al. (Socket)

RELEASES:

• Deno 2.5 - You can now create sets of permissions in deno.json, Deno.test gets some DX improvements, and deno bundle gets a programmatic API so you can script the bundling of your app, along with much more.

• ESLint v9.35.0 - Has a new rule (preserve-caught-error) for disallowing the loss of an originally caught error when re-throwing custom errors.

• Node.js v24.8.0 (Current) - Now supporting inspection of HTTP/2 network calls in Chrome DevTools.

• Electron 38 - Mentioned last week, but now has an official blog post.

• Storybook 10 is now in beta. The big change is it's going ESM only.

• Ember 6.7, Rspack 1.5.3, Expo Router v6, Fastify 5.6

📖 Articles and Videos

The Missing Link in JavaScript Tools? - Marvin ponders whether today's fractured toolchain for templates, CSS imports, JSX, and numerous other non-standard enhancements to JavaScript could be unified into a single pipeline.

Marvin Hagemeister

Finally, Safe Array Methods in JavaScript - arr.sort() will sort your array in place, whereas ES2023's arr.toSorted() will return a new, sorted copy of arr. There are several such methods you might prefer to use.

Matt Smith

Secure Your Agentic Apps with Auth for GenAI - Secure your agentic apps with features like User Authentication for AI agents, Token Vault, and more with Auth0's Auth for GenAI (exclusively in Developer Preview).

Auth0 sponsor

An Interactive Guide to TanStack DB - TanStack DB offers an embedded client‑side database that uses differential dataflow to power live, relational queries, sub‑ms incremental updates, and optimistic writes. This tutorial leans on using it with React, but TanStack DB works alongside Vue, Solid, and Svelte as well.

Maxi Ferreira

📺 Handling 500 Million Clicks with a $4 VPS - Behind the scenes of a Node-backed site that went viral. Andrew Schmelyun

📄 How To Set Up Express.js 5 For Production in 2025 Jan Hesters

📄 Building Microfrontends with Module Federation and Vue Alex Opalic

📄 How Shopify Migrated to React Native's New Architecture Thiago Magalhaes (Shopify)

🛠 Code & Tools

Andromeda: The Newest JavaScript Runtime on the Block - A new JavaScript and TypeScript runtime built around the Rust-powered Nova engine. It's still early days but they're promising a lot: native single file compilation, a GPU-accelerated 2D Canvas API, low runtime overhead, interop with Rust, memory safety, WinterTC compatibility, and cross-platform support.

Andromeda Team

BlazeDiff: 'Blazing-Fast' Pixel-by-Pixel Image Comparisons - The creator was happy with the established pixelmatch library for doing image comparisons, until it got too slow for the scale he wanted. Here's the story of how he came up with a faster alternative.

Teimur Gasanov

Unlock the Power of MCP Servers - Clerk shows how MCP servers let AI apps access data securely with OAuth - complete with a Next.js demo.

Clerk sponsor

Feedsmith 2.0: Feed Parser and Generation Library - As well as parsing feeds, you can also create RSS, Atom, JSON Feed, and OPML files with many common namespaces (iTunes, Podcast, Media RSS, Dublin Core, etc.) There's a quick start tutorial for using it both in browsers or Node.js. GitHub repo.

Maciej Lamberski

React Bits: 100+ Creative, Animated React Components - If you want a bit of visual pizzazz in your project, this is for you. The components span from a variety of text effects to general animations, a 'chroma grid', bouncing cards, distortions, and more. GitHub repo.

David Has

• Ink 6.3 - Use React to build CLI apps, as used by Claude Code, Gemini CLI, and many other apps.

• Tricolore 0.1 - Visualize ternary compositions with choropleth maps. Live demo.

• ts-to-zod 4.0 - Generate Zod schemas (v4) from TypeScript types/interfaces.

• Confirmal 1.3 - Turn FormData into real objects with TypeScript inference.

• 📊 Chartbrew 4.3 - Create live reporting dashboards.

• ow 3.0 - Function argument validation for humans.

• uuid 13.0 - Generate RFC9562 compliant UUIDs.

• Fresh 2.0 - Deno-powered Web framework.

🎵 Let's Get Musical

SpessaSynth: SoundFont2-Based MIDI Player and Synthesizer - If you think typical browser-played MIDI files sound terrible, you're right - but try this! It uses a SoundFont sample driven approach to play MIDI files in a predictable fashion, and also includes an editor/visualizer if you need it. The live demo is quite striking.

Spessasus

While we're on the topic, here are some other neat music related JavaScript projects we've enjoyed over the years:

• alphaTab - A full on music notation and guitar tab rendering library for building complete musical apps (above).

• chiptune3.js - A bit like SpressaSynth (also above) but for playing module file music. Live demo.

• Tone.js - An easy way to use the Web Audio API to create music in the browser. Someone used it to recreate the famous THX 'deep note' sound.

• 🎸 SVGuitar - A library to render SVG guitar chord charts.

• JZZ.js - A JavaScript MIDI library that hides a lot of complexity behind its chained syntax when you need to work directly with MIDI. (The keyboard logo at the top left of its homepage is a neat easter egg.)

• Strudel - A live-coding environment in the browser for generating pieces of music with simple, chained JavaScript expressions.

#​751 - September 5, 2025

Read on the Web

JavaScript Weekly

Mediabunny: A Complete Media Toolkit for JavaScript - Supporting both browsers and Node.js, this library lets you read, write and convert popular media file formats (e.g. MP4, MP3, and more) without needing to lean on dependencies like FFmpeg. You can make thumbnails, extract metadata, write code that gets converted into a video, and more. GitHub repo.

Vanilagy

Why Do Browsers Throttle JavaScript Timers? - Did you know the zero in setTimeout(0) doesn't really mean zero? Browsers clamp timers to at least a few milliseconds or more, slowing down code that relies on them. Luckily, there are alternative options, which Nolan demonstrates and benchmarks.

Nolan Lawson

Boost Coding Productivity with AI-Assisted Tools & Agents - Join Steve Kinney for this course looking at how best to harness AI for faster, higher-quality code. Learn how Cursor and Claude Code can be used to handle project plans, carry out inline edits, and perform larger background tasks - all adhering to the guidelines you set.

Frontend Masters sponsor

Ripple: A New, In-Development TypeScript UI Framework - A new framework aiming to take the best parts of React, Solid and Svelte, and combine them into a single package. Notably, it comes from someone who worked on React and Svelte, as well as author of Lexical and Inferno, so it's worth a look. There's more info on the GitHub repo.

Dominic Gannaway

IN BRIEF:

• The What's New in Viteland: August 2025 recap presents a handy roundup of what's going on with Oxlint, Vite, Vitest, Rolldown, and related projects.

• The Angular team has a big summer update too, covering zoneless change detection, new animation features, AI integrations, better debugging, and more.

• Thoughtbot shares its list of upcoming JavaScript conferences for 2025.

Product for Engineers Newsletter - Build better products, not just better code. Learn how to build features users love. Subscribe for free

PostHog sponsor

RELEASES:

• Deno's Fresh framework is now out in Fresh 2.0 Beta form. It can now optionally run as a Vite plugin which opens up numerous new possibilities.

• Electron 38.0 - The cross-platform desktop app framework. Now using Chromium 140 and Node 22.18 with V8 14.0.

• Ember 6.6 - The framework "for building ambitious web applications."

• Node.js v20.19.5 (LTS)

📖 Articles and Videos

Google Chrome Turns 17: A History - A fantastic walkthrough of Chrome's origins and its evolution over the years. Addy looks at key milestones (multi-process architecture for example), security, its steps into the world of AI, and more.

Addy Osmani

💡 On the topic of Chrome, Top Chrome APIs Every Developer Should Try covers a variety of Chrome-only JavaScript APIs, most of which I wasn't aware of.

Lean for JavaScript Developers - A comprehensive introduction to Lean, a theorem prover and language for creating formally verified code that Dan Abramov has really been getting into recently. "I've never written code alongside proofs like this before. Have you?"

Dan Abramov

AI Writes Code. Wallaby MCP Makes Sure It Actually Works - Give your AI agent live execution data, coverage, and real-time insights to generate tests and code with confidence.

Wallaby Team sponsor

Getting Accurate Text Lengths with Intl.Segmenter - A useful tip for when .length just isn't returning what you'd quite expect..

Sangeeth Sudheer

Making XML Human-Readable Without XSLT - Jake gets niche, but sets JavaScript to good use here.

Jake Archibald

📄 Stress-Testing Biome's noFloatingPromises Lint Rule Dimitri Mitropoulos (Vercel)

📄 How to Optimize Third Party Scripts with Web Workers and Partytown Jakub Andrzejewski

📄 Redux without React: State Management in Vanilla JS Moritz Kröger

📄 Functional Custom Elements the Easy Way Ginger (Piccalilli)

🛠 Code & Tools

Peaks.js 4.0: UI Component for Interacting with Audio Waveforms - A project originally spawned from the BBC's R&D department, Peaks renders audio waveforms to a canvas element and allows scrolling, zooming, and the sort of things you might otherwise see in an audio editor. LGPL licensed.

Chris Needham et al.

💡 There are other options in this space too, including the newly released Waveform Renderer 1.0 (complete with interactive demo) which is entirely focused on waveform rendering, as well as Wavesurfer.js.

Redux Toolkit 2.9: The 'Batteries-Included' Toolset for Redux - The long-standing toolset for working with Redux for state management gets a performance update with a rewrite of RTK Query's subscription and polling systems, automatic aborting of in-flight requests when a cache entry is removed, and more.

Mark Erikson

react-window 2.0: Render Large Lists of Data Quickly - A component library for rendering large lists of data quickly and without the performance problems that often go along with that. There are several examples to check out, and React 18 is now required. (Tanstack Virtual is another option to consider in this space.)

Brian Vaughn

• serverless-http 4.0 - Use your existing middleware framework (e.g. Express, Koa) on AWS Lambda.

• 🖋️ Signature Pad 5.1 - Canvas-based smooth signature drawing control.

• Tinypool 2.0 - Minimal Node.js worker thread pool implementation.

• gRPC Web 2.0 - JS implementation of gRPC for browser clients.

• Jasmine 5.10 - Testing framework for browsers & Node.

• NodeBB 4.5 - Node.js-powered forum system.

• Watt 3 - Node.js application server.

✉️ From the Inbox

For a variety of reasons - not least taking a vacation in August (oops!) - I have a backlog of fantastic submissions from people that I want to share separately:

• 🎨 Eyecons is a VS Code icon theme that automatically adapts the color of icons to fit your editor's main theme - well, from this list anyway.

• TypeScript Result brings a Result type into play to help you handle errors in a more type-safe way.

• Vue Log Arsenal is a plugin that adds a variety of logging directives for Vue 3 apps to use directly in elements, like this, for example.

• Michael Sweeney shows off 'the JavaScript equivalent of a magic trick' using functions acting as primitives and nested proxies that remember their ancestry.

• StateLayer is a forthcoming declarative 3D component framework whose homepage is a live demo. There's also a getting started tutorial showing how to build your own 3D scene from scratch.

• fp-filters is a curated suite of over a hundred common-use filter functions that can be used in a functional programming style.

#​750 - August 29, 2025

Read on the Web

JavaScript Weekly

An Illustrated Guide to Big O and Time Complexity - A fantastic JavaScript-oriented, interactive, visual essay about Big O notation and its role in describing algorithmic complexity. This is a beautiful bit of work, even if you're already wise to O(log n) and O(n^2).

Sam Rose

💡 Sam is making a name for himself with his interactive essays - check out the load balancing, memory allocation, hashing, and bloom filter ones too.

JavaScript's Trademark Problem - Dr. Axel discusses Oracle's hold over the 'JavaScript' trademark, including the history and present-day legal attempts to challenge Oracle. Fireship has also just published ▶️ a video about the battle and there's now a GoFundMe to raise funds to continue the fight.

Dr. Axel Rauschmayer et al.

Tests Are Dead. Meticulous AI Is Here - Meticulous creates and maintains a continuously evolving E2E UI test suite with zero developer effort. Built on Chromium with a deterministic engine, it's the only testing tool that eliminates flakes. Relied on by Dropbox, Notion, and Wiz.

Meticulous AI sponsor

New in ESLint v9.34.0: Multithread Linting - A common feature of tools like Rslint, Biome, and Oxlint, is being 'Nx times faster' than ESLint, but the latest ESLint has a trick up its sleeve and can now process multiple files at the same time, dramatically reducing lint times for large projects.

Francesco Trotta

IN BRIEF:

• Daniel Rosenwasser proposes that TypeScript 6.0 should have --strict on by default. You can learn more about what's planned for TypeScript 6.0 here.

• Malicious versions of Nx, along with some supporting plugin packages, were published to npm - more details on affected versions.

• Remix v3 is set to drop React, instead using its own fork of Preact.

• Codecs are a new Zod API for defining bidirectional transformations between two types.

• 🇺🇸 CascadiaJS is a conference taking place September 18-19 in Seattle, WA.

RELEASES:

• Rspack 1.5 - The fast web bundler improves barrel file optimization, has a faster file system watcher, improved browser support, and more. It's a big release.

• Node.js v24.7.0 (Current) - A step forward for cryptography, both with Web Cryptography API support and post-quantum standards.

• Electron 37.4, Prisma 6.15.0, Ink 6.2.3

📖 Articles and Videos

Speeding Up the JavaScript Ecosystem: Semver - The latest in Marvin's multi-year series of posts on optimizing heavily used parts of the JavaScript ecosystem: "During the installation process, package managers run a bunch of semver comparisons. The semver library used in npm, yarn and pnpm can be made around 33x faster."

Marvin Hagemeister

Say Bye with JavaScript Beacon - The Beacon API has been supported in all mainstream browsers for years now and provides a way to send a guaranteed (even if a page is being unloaded) non-blocking request to a web server when no response is needed.

HemathKumar R

Secure Your AI Agents So That You Can Protect Your Users - Whether you have a B2B or B2C use case, Auth0 is a full IdP that provides robust security like MFA and continuous threat monitoring.

Auth0 sponsor

How We Migrated Our Monorepo to Node Type Stripping - Since v23.6 (and in LTS since v22.18.0), Node has supported running (most) TypeScript code by stripping the types out first. One team shares the challenges encountered and what the end benefits were.

Stuart Dotson (Calm)

You No Longer Need JavaScript (For Many Frontend Things) - A neat look at some of what plain HTML and CSS can achieve in terms of effects and techniques for which you might have once relied upon JavaScript.

Lyra

📄 Understanding Promise.any(): When One Success is Enough - Given multiple promises, resolve as soon as just one fulfills. Matt Smith

📄 The Struggle of Wrapping a JavaScript Game for Desktop - The author explains why they finally settled on NW.js. JSLegendDev

📄 Speeding Up Firefox Local AI Runtime - How Firefox accelerated inference by replacing the WASM-based ONNX runtime that powers Transformers.js with a native C++ counterpart. Ziadé, Adenot, and Guelton

📄 Unit Formatting with Intl in JavaScript Raymond Camden

📄 Exporting a Cloth Simulation from Blender to an Interactive Three.js Scene Joshua Guo

📺 Coming in Angular 21: HttpClient Built In by Default Igor Sedov

🛠 Code & Tools

Cornerstone3D 4.0: Build Web-Based Medical Imaging Apps - A set of JavaScript libraries to build things like this 3D CT scan viewer, PET-CT scan viewer, and much more besides. There's a lot to this project, along with numerous tutorials.

Open Health Imaging Foundation

ImageJS 1.0: Image Processing and Manipulation Library - A library for resizing, cropping, filtering, color adjustments, and numerous other image transformations which works in Node.js and the browser (supporting JPEG, PNG, BMP and TIFF - thanks to pure JS dependencies like fast-jpeg and fast-png). v1.0 brings TypeScript support and a more intuitive API. GitHub repo.

ImageJS Team

The Best Way for Web Developers To Track Key User Flows - Check out User Journeys, a new approach to connecting technical performance to user engagement in your web apps.

Embrace sponsor

Obs.js: Context-Aware Web Performance for Everyone - Uses the Navigator and Battery APIs to get contextual information about your users' connection strength and battery status so you can adapt your site/app to the environment or collect the data for analysis.

Harry Roberts

📊 SveltePlot: A Visualization Framework for Svelte - It's still in alpha but its API is inspired by a similar plotting library by Observable and built on top of D3. There are plenty of examples in the docs.

Gregor Aisch

• Repomix 1.4 - Pack an entire repository into a single, LLM-friendly file. v1.4 adds the ability to integrate commit history.

• MikroORM 6.5 - TypeScript ORM for Node based on Data Mapper, Unit of Work and Identity Map patterns.

• 📄 jsPDF 3.0.2 - Client-side JavaScript PDF generation for everyone.

• Faker 10.0 - Generate fabricated data to your heart's content.

• Tiptap 3.3 - Headless, framework-agnostic rich text editor.

• RxDB 16.18 - Offline-first, reactive database for JS apps.

• Denops.vim 8.0 - Write Vim/Neovim plugins with Deno.

🎁 Some Bonus Items

• Intl Playground is a handy site to get a quick look at how the different options on Intl.DateTimeFormat present in real life.

• 📺 The folks who created the epic, well-produced ▶️ Vue.js documentary, ▶️ React documentary and ▶️ Node.js documentary are back with ▶️ a movie-length documentary all about Python.

• Talking of Python, Pyodide is a port of CPython to WebAssembly that can be used both in the browser and from Node.js.

• 🕹️ Jeff Schomay is creating a JavaScript roguelike game called Thunder Lizard and decided to see what would happen if he used AI to turn his ASCII renders into full graphics live and on-the-fly. Fun, but sounds expensive!

• GitHub has added WebP image support across its site. It was a little flaky till now.

• 🎵 Need some music for programming? A fantastic design for a text-only site.