I think its killer use case is actually embedded in non-web places. Tree Sitter parsers require arbitrary programs to be able to parse arbitrary languages. WebAssembly is a natural way to achieve that: write your parser in any language, compile to WebAssembly, use that result in any supported editor. You get sandboxed execution and arbitrary compute.

It has to compete with more domain-adapted use cases though. Does WASM make more sense than eBPF for packet filtering? It doesn't seem to make more sense than JavaScript for making websites. Maybe it makes more sense for deploying edge services (which IIUC is the main use case for WASI).

I think I've seen you comment this on every recent WASM post, and I'm really wondering what you think breakthrough success looks like for a low-level technology like WASM?

Do you expect everyone to hand-code their websites in WASM? Do you expect every webapp be cross-compiled to WASM?

From where I'm standing, WASM is extremely successful in its specific niches: in enabling islands of high-performance in otherwise web-based software, and in sandboxing plugins to native apps/servers.

It's already a breakthrough in my opinion.

Many things are possible that weren't possible before. For example, I was able to compile the Dart VM (the compiler + analyzer + VM) to wasm and run it on the web: https://github.com/modulovalue/dart-live it supports hot reload and many other cool features. It runs essentially everywhere and it's a very bare proof of concept for a fully integrated programming development system.

The problem is that things just take time if you have to coordinate across a bunch of languages and teams while trying to make everyone happy.

To give you a sense of what else is coming: the wasm ecosystem is moving towards supporting a component model. Eventually you'll be able to import any piece of code from any programming language that supports it. Wasm interface types will make that possible.

It's a silent technology, but I'd argue it has broken through in that most of us already use it daily without knowing. Figma, Google Sheets, Disney+, Prime Video, and much more all have WebAssembly somewhere in their stack.

WebAssembly is used in all sorts of ways.

It's used heavily by major web apps like Figma, it's used to run non-Javascript languages on Cloudflare Workers, many compute-heavy web libraries rely on Wasm modules, many web games rely on Wasm, it's used for safe plugins in some native apps like Microsoft Flight Simulator, amongst other use cases.

It has, but its usually just an optimization, so goes unnoticed

WASI stands for WebAssembly System Interface.

It has little to do with the webassembly in the browser.

I use it to extend a native application, for example. No browser in sight at all.

WebAssembly doesn't beat JavaScript in performance, and that is embarrassing.

I mean, it’s another tool. It doesn’t really make an entirely new kind of web app possible, but it’s useful for some specific compute-heavy tasks (with limitations like JS<->WASM being slow). It’s also useful for running not-JS in the browser; I’m building a lighting console with a web UI distributed over multiple devices, and being able to use the exact same structs/representation and algorithms on server and client is pretty neat. It’s like Node, but in reverse! But none of this is cause for paradigm shift, so I don’t think seeing a ”breakthrough” really is relevant.

You said the exact same thing a couple days ago. You don't know what you don't know.

WebAssembly has been a great success thanks to its excellent initial design.

for me its undebuggability.

-"hey, look at our C Rust FORTRAN to WASM translator, blahblah"

-"uhm, cool, how do I debug it?"

-"yeah...about that...you cant!"

I'm building a game where you learn to program golang or python and it all runs in webassembly, this way any student chromebook can just pick up and go.

That feels pretty revolutionary, no need to setup your local system to get core concepts.

Even have plans to use postgres in WASM (pglite), and I know a few real time apps use sqlite in WASM.