A cool paper from OOPSLA '25 — An Empirical Evaluation of Property-Based Testing in Python → dl.acm.org/doi/pdf/10.1... Some interesting findings: - "Each property-based test finds about 50x as many mutations as the average unit test" - "76% of mutations were found within the first 20 inputs"

Ever thought about writing #WebAssembly by hand? 🤔 Authors Patrick @dubroy.com and @marianoguerra.org think it's crucial for learning. They join #WasmAssembly host Thomas Steiner to discuss their ebook, "WebAssembly from the Ground Up" → goo.gle/3Ln67Pp

Did you know that Microsoft MakeCode (a Scratch-like coding environment) supports a variant of TypeScript called "Static TypeScript"? github.com/microsoft/px... Also described in a 2019 MPLR paper: www.microsoft.com/en-us/resear...

jumpscared by my own research paper appearing halfway down this blog post

Periodic reminder (since I apparently don't talk about it enough) — If you are interested in a hands-on way to learn #wasm, check out the book that @marianoguerra.org and I wrote together!

Working on a diagram for an upcoming @wasmgroundup.com blog post.

A blog post from last year, which I never posted here — Bytecode VMs in surprising places → dubroy.com/blog/bytecod...

Looking forward to this tomorrow!

If you're interested in UI frameworks/architectures, @raphlinus.bsky.social's writings on the evolution of Xilem (Rust UI toolkit) are an incredible resource: github.com/linebender/x... Covers details basically all the modern paradigms/toolkits: React, SwiftUI, Flutter, Compose, ImGui, etc.

I'm kinda surprised how hooks as a concept have taken off beyond React. It's a clever solution with some nice properties, but…also kind of weird? Hidden state, and generally kind of hard to reason about and explain.

An interesting development in the past 10–15 years is the co-evoluation of PLs and UI toolkits: • JSX for React (then later other toolkits) • Swift 5.1 added a bunch features for SwiftUI: www.swiftbysundell.com/articles/the... • Kotlin's Composable functions: medium.com/androiddevel...

ICYMI: @marianoguerra.org and I had a fun conversation with Thomas on the WasmAssembly podcast, all about our book @wasmgroundup.com. You can watch it here, or find it wherever fine podcasts are sold.

📢 New #WasmAssembly podcast 🎙️ episode: #WebAssembly from the Ground Up with @dubroy.com and @marianoguerra.org. Learn how they're teaching #Wasm by building a compiler in JavaScript and why writing Wasm by hand is crucial! 🍿 www.youtube.com/watch?v=dRdD... 🎧 wasmassembly.libsyn.com/webassembly-...

The "Inside Flutter" page from the @flutter.dev docs is a joy: docs.flutter.dev/resources/in.... Would love to see more libraries document their philosophy/approach and "what makes us different" like this.

Thinking about fine-grained, reactive tree transformations…but *not* targeting the DOM. Like @solidjs.com, but for arbitrary JSON output…does this exist already??

🤔

This place is not a place of honor…

I'm teaching 𝗪𝗿𝗶𝘁𝗲 𝘆𝗼𝘂𝗿 𝗼𝘄𝗻 𝘁𝗶𝗻𝘆 𝗽𝗿𝗼𝗴𝗿𝗮𝗺𝗺𝗶𝗻𝗴 𝘀𝘆𝘀𝘁𝗲𝗺(𝘀)! again. I'll be posting the videos & tasks on YouTube too. In the first lecture, I explain what's a tiny system, why write one and show plenty of demos! 🎞️ Playlist: www.youtube.com/playlist?lis... 👉 More info: d3s.mff.cuni.cz/teaching/npr...

TIL: [JS] Explicit resource management → github.com/pdubroy/til/... Don't miss the getter trick! It's super helpful and not well-documented.

I like this — A case for learning GPU programming with a compute-first mindset: themaister.net/blog/2025/10...

Been a big fan of mise for a while now, but now I discovered that it can replace make? *swoon* mise.jdx.dev/tasks/task-c...

You can just make things on the web collaborative by adding a single HTML attribute...

TIL: WebAssembly library initialization patterns →https://github.com/pdubroy/til/blob/main/js/2025-10-05-WebAssembly-library-initialization-patterns.md

JS folks: best way to deal with a public API (in an NPM package) going from sync → async by default? 1️⃣ New major version (`doXyz` becomes async; add `doXyzSync`) 2️⃣ New major version, remove `doXyz`, add `doXyzSync` and `doXyzAsync` 3️⃣ Something else?

Going for a bike ride remains one of my most powerful debugging techniques.

Man, I still really like a lot of the ideas behind @cuelang.org. (But I need to find a good excuse to use it properly to see how it fares in practice.)

oooh, this looks super useful.

Whoah. TIL that yt-dlp (the command line video download tool) includes a crude JS "interpreter" (~1k lines of Python). github.com/yt-dlp/yt-dl...

"Benchmarks are not numerology. Their results are not a divine revelation. Benchmarks are experiments. Their results are meaningless without interpretation and validation." Microbenchmarks are experiments: mrale.ph/blog/2024/11... by @mrale.ph

The shape of things to come.

TIL: FinalizationRegistry → github.com/pdubroy/til/...

Can anyone recommend JS libs that have a good approach to managing Wasm/WebGPU/WebGL resources? We have more options these days (FinalizationRegistry / `using`) but I’m curious how people are making use of those in libraries.

PL folks — For @ohmjs.org, I’m looking at how to support fully incremental pipelines (eg parsing → codegen, all incremental). I know about Salsa (github.com/salsa-rs/salsa); what else should I be looking at?

Finally got around to reading Build Systems à la Carte (dl.acm.org/doi/pdf/10.1...), it's really great (like everyone says). I love papers like this, that take a well-known, messy, unloved area and propose a useful organizing principle for it.

Ha, the @convex.dev landing page shows a live example with a bug and prompts you to fix it. Not sure I've seen something like this before but I like it!

12 exciting live-programming projects will be presented at LIVE this year. It's free, online, and coming up soon! Sat 9/27: Videos premiere Sat 10/4: Q & A and discussion over Zoom Details on projects are up already at liveprog.org; more schedule & links coming soon. Hope to see ya there!

Hey everyone, just FYI: After investigating, we do *not* believe that ohm-js, or any other package under the @ ohmjs namespace, is affected by the Shai-Hulud worm or any of the recent npm supply chain attacks.

TIL: [JS] Faster formatting and linting → github.com/pdubroy/til/blob/m...

❤️ the old Ontario Hydro logo, what a beaut

PL friends — A reader of @wasmgroundup.com asked: "Is there a book that can help with reading the mathematical notation in the web assembly core spec?" The spec itself suggests TAPL, but I'm curious if anyone has any other suggestions.

Thanks to @yoshikiohshima.bsky.social I found the Alan Kay story that this reminded me of. From "The Early History of Smalltalk": worrydream.com/EarlyHistory...

"The second you realize a technology has a hard requirement that individuals independently exercise responsibility or self-control, with no obvious immediate gain for themselves, it is almost certain that said technology is unsalvageable in its current form." news.ycombinator.com/item?id=4521...

But will it work in the EU? 🤔

Just deleted the GMail & GCal apps from my phone, feels good. Moved over to Fastmail a couple weeks ago and don't see any reason to go back.

A few quotes about Steve Jobs from "Valley of Genius" by Adam Fisher.

TIL: Lightweight TypeScript support in Node → github.com/pdubroy/til/...

Seems like an appropriate time to re-share the @aaronboodman.com thread. "Chrome was delivered without any sprints at all" xcancel.com/aboodman/sta...

TIL: [JavaScript] publishConfig in package.json → github.com/pdubroy/til/...

New poster for my home office.

From the author of Pandoc — "I'll go through the six features of Markdown that I think have created the most difficulties" Beyond Markdown: johnmacfarlane.net/beyond-markd...