A real component model is a separate development and cannot be blindly tied to a particular ecosystem. Otherwise, its main purpose of providing easy interoperability between different ecosystems is totally lost.
I do not know why WebAssembly committee thinks that shoving-in CORBA-like monstrosity is even an acceptable idea. Let's keep WebAssembly lean and fast! Anything extra can (and should) be implemented by other technologies.
If you have a host system where you want to expose APIs in an language-agnostic way, IDLs are the best way to do that.
You're also conflating the core WebAssembly work with the WASI work. There is some overlap in people, but WASI is developed separately.
I’ve written Wasm and component model wat extensively over the last decade to develop tests for Wasmtime, and even for an expert it’s a bad experience.
Wit syntax is easy to read and write by hand. There are high quality parsers that can transform it to and from the binary or wat format as needed, and code generators for a wide range of languages. It’s a way, way better experience in every way to deal with wit compared to the wat format.
Now it feels like it moved from "what would we need to get things done and achieve our goals?" to "what could be done and which goals could we achieve?"
Maybe I am missing something, but are the recent changes something that people requested?
Also to be fair "just copying" works really really well, especially for standards. The primary goal of standardization is not to invent something new, but to have a target that isn't constantly moving.
If you want to build something new and better do that, and if you are ready to build a standard based of it which is very valid. You can also build them together, and CloudABI which they mention as inspiration in their readme for example did it that way. All valid paths.
But you want to start out simple and something common so that people that make use of the standard have an easy time to implement it. After all having more than one implementation is why you need a standard. Otherwise it's maybe a specification, which again, fair enough.
I can stand behind not copying Unix until the end of time, but "Unix" is a common target that people know how to implement and use. And while not even the authors of Unix claim it's great or even good it is something that people already implement (often enough even when not targeting anything unixy at all) so if your goal is to create a standard that those people can target then abandoning that does seem like a wrong move.
Sometimes bad designs stick around due to pure inertia
That makes me very suspicious of wasiv3. Funny enough, I already implemented a bunch of the promises (pun not intended) and think that freestanding wasm with custom integrations is the more likely future.
The promise of wasi components has not been fulfilled. The market wants to hotload and link artifacts dynamically. The wasi project requires insider wizardry to use it that way: the offering has been statically linking components before you ship. Defeating 99% of the use cases.
I do not like that this has been worked on in the shadows.
- Many standing meetings organized around SIGs, all on the public community calendar: https://calendar.google.com/calendar/u/0/newembed?src=events...
- A dedicated Zulip: https://bytecodealliance.zulipchat.com/
- Conferences organized around exactly these topics: Wasm Day, WasmCon, Wasm I/O, and the Bytecode Alliance Plumbers Summit
- CNCF projects: wasmCloud, Spin
- Blogs, many with recordings, summaries, and transcripts: https://bytecodealliance.org/articles/the-road-to-component-..., https://wasmcloud.com/community/, https://spinframework.dev/blog/index
If you want the architectural direction straight from the source, Luke Wagner's keynotes are the best place to start:
- "What is a Component (and Why)?" (WasmCon 2023): https://www.youtube.com/watch?v=tAACYA1Mwv4
- "The Path to Components": https://www.youtube.com/watch?v=phodPLY8zNE
- "Towards a Component Model 1.0" (Wasm I/O 2026): https://www.youtube.com/watch?v=qq0Auw01tH8
I mean this, though - what else would you like to see to try and make the content and process more accessible? Are there communities that are doing this really well that we could use for inspiration?
At 18:00 the speaker states something like "It should not be Systems Interface but Standard Interfaces" which honestly sounds like a different project. As an implementer or even as just a user in general, can it be trusted that tomorrow it isn't something completely different? Seems like an odd standard to follow.
It's quite specific though as I'm working on support programming in the browser.
If you are not deep into letting a very specific kind of user extend, it's probably overkill.
Even then it's a very VERY niche thing because it has to be simultaneously :
- someone who is opinionated about a programming language (either because they know too much, i.e. expert, or not enough, i.e beginner)
- is dedicated enough to want to try to build something on top of an existing system
- does not want to bother with solutions you mentioned
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.
Is this really a representative use-case of WASM/WASI? Would'n it be much better to compile Dart to WASM (the Dart SDK even supports "dart compile 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 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).
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.
The JS code had been written carefully to avoid allocations, and also avoiding the built-in JavaScript BigInt. I rolled my own BigInt instead using an array of numbers. Each number, despite being a double, was basically a 48-bit integer. Long multiplication requires splitting a 48-bit integer into two 24-bit integers so an intermediate multiplication result will fit in 48 bits.
The C version used 32x32=64-bit integer math. (Would have been nice if WASM had supported 64x64=128-bit multiplication)
Even with the overhead of using doubles instead of integers, the JavaScript and C versions ran at nearly the same speed. I think the C version was slightly faster, but not significantly. The C version took a lot longer to load, as it had to instantiate a Webassembly object, and had to run glue code to copy things in and out of Webassembly memory.
https://hacks.mozilla.org/2026/02/making-webassembly-a-first...
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 has been a great success thanks to its excellent initial design.
-"hey, look at our C Rust FORTRAN to WASM translator, blahblah"
-"uhm, cool, how do I debug it?"
-"yeah...about that...you cant!"
So wasm is a really strange compilation target for systems programming languages.
I mean there _are_ ways to debug it in a browser but they sort of suck.