I am unfamiliar with this project and only skimmed this post but if this uses Rust for the main binary blob it should be possible to have the main thread blob shared with the other threads even with the blocking.

The blog post cites the concern that malloc could block, however when Rust's standard library is compiled with support for atomics enabled the Rust allocator's locking implementation busy loops instead of waiting on the main thread.

See the comment in the Rust source here: https://github.com/rust-lang/rust/blob/77a4fb62f70c6ea05e182...

This means that if care is taken to avoid any other code that makes the main thread wait it should be possible to use a single shared binary instead of the more convoluted approach presented in the blog post.

If you’re poking around WASM consider falling down the Component Model rabbit hole:

https://github.com/WebAssembly/component-model/blob/main/des...

Threading is actively being worked on right now (to be released in 0.3.x, soon), and some changes just made their way into LLVM as well:

https://github.com/llvm/llvm-project/pull/175800

Seems like Theseus is not using OffscreenCanvas yet. Should be a good fit for something that runs off the main thread. Graphics can be rendered from a background worker thread directly to the screen without the involvement of the browser main thread at all.

https://developer.mozilla.org/en-US/docs/Web/API/OffscreenCa...

When I clicked, I thought this was going to be about the Theseus operating system [0]. Running win32 programs on it would have been ... interesting.

It too uses WASM, but for running non-Rust programs in sandboxes. Everything else is Rust. Hmm.. Last updated in 2024 though.

0: https://github.com/theseus-os/Theseus

It's refreshing to see those kind of projects coming back on HN. Pretty awesome to see your example (https://evmar.github.io/theseus/) fit in about 1MB when a lot of those wasm projects can be super heavy (like libreoffice which is 50MB after brotli compression)

I miss the days when this would just have been named win2wasm.

These branded projects become difficult to remember when everything has a random non-mnemonic name.

Seeing minesweeper recompiled to run in the browser is awesome.

The pain points about threading in the browser and debugging wasm are the two problems I ran into on another project. I hope we can get some improvements in both areas because wasm would be a lot easier to work with if developers didn't have to fight both of those topics.

I also tried doing multithreaded wasm in Rust, and I got some weiiiiird errors. Definitely not stable yet.

This is a big deal when/if it's working, to me at least. Where can I contribute?

An interesting learning project, but not actually usable.

https://github.com/danoon2/Boxedwine looks interesting in this space, but unfortunately it can't really run anything remotely modern in practice (though if you're looking at 20th century Windows software it will likely be capable of running it).