jco

I use @wasmer/wasi for my npm package `trealla` (wasm port of a Prolog interpreter). For the most part I'm pretty happy with it, but the file size is quite large[1] (taking up around half my bundle size), and it looks like @wasmer/sdk is even larger (wasmer.sh downloads a 1.7MB gzipped wasm binary that I assume is the runtime). It's a tough sell to the frontend folks when my package is this big... currently I have my eye on jco[2] which I hope will be much lighter. No shade intended towards the Wasmer folks, I appreciate the work they've done. [1]: https://bundlephobia.com/package/@wasmer/wasi@1.2.2 [2]: https://github.com/bytecodealliance/jco

The roadmap I linked above. The WASI folks have done a poor job at communicating, no doubt. Just for you I did some googling: see here[0] for the current status of WASI threads overall, or here[1] and here[2] for what they are up to with WASI in general. In this PR[3] you can see they enabled threads (atomic instructions and shared memory, not thread creation) by default in wasmtime. And in this[4] repository you can see they are actively developing the thread creation API and have it as their #1 priority. If folks want to use WASIX as a quick and dirty hack to compile existing programs, then by all means, have at it! I think that's great. Just know that your WASIX program isn't going to run natively in wasmtime (arguably the best WASM runtime with the strongest long-term outlook), nor will it run in browsers, because they're going to fol

The component model is already shipping in Wasmtime, and will be stable for use in Node.js and in browsers via jco (https://github.com/bytecodealliance/jco) soon. WASI Preview 2 will be done in December or January, giving component model users a stable set of interfaces to use for scheduling, streams, and higher level functionality like stdio, filesystem, sockets, and http on an opt-in basis. You should look at wit-bindgen (https://github.com/bytecodealliance/wit-bindgen) to see some of the languages currently supported, and more that will be mature enough to use very soon (https://github.com/bytecodealliance/componentize-py) Right now jco will automatically generate the JS glue code which implements a Component Model runtime on top of the JS engine's existing WebAssembly implementation. So, yes, Components are a composition of Wasm Modul

Thank you! To your point, the primary consideration for choosing the languages is their support for WebAssembly, and WASI in particular. Due to Spin's heavy use of WASI and the component model, languages that have first party support in the WIT bindings generator (https://github.com/bytecodealliance/wit-bindgen) are the easiest to implement, followed by languages that can be built on top of the support for those with first party support. For example, the JavaScript support is built by embedding QuickJS (in particular, Shopify's Javy project — https://github.com/fermyon/spin-js-sdk), which then uses the Rust SDK. (As a side note for the JS support — adapting QuickJS has been extremely helpful in getting JS support out; however, we are in the process of rebuilding the JS runtime using SpiderMonkey (with which a few people on the team have s

That's really useful. This page in particular: https://github.com/bytecodealliance/jco/blob/main/EXAMPLE.md Being able to run "jco wit cowsay.wasm" to see what interfaces that .wasm file provides solves a problem I've run into a bunch of times in the past.

To run a JavaScript interpreter (spidermonkey, in this case) in Wasm, as well as running that same wasm in a JS engine, you want to look at `jco` https://github.com/bytecodealliance/jco The component model tooling is getting very close to maturity and will solve many of these problems.

You can use jco to both compile a JavaScript module into a WebAssembly Component (with spidermonkey running as wasm inside), and to generate a Javascript embedding for that component. This solves all of your problems except for untrusted code looping forever, and that’s something which could be added to spidermonkey.wasm. https://github.com/bytecodealliance/jco You can also run these same components server-side with Wasmtime.

`jco componentize` turns a JavaScript module into a WebAssmebly component: https://github.com/bytecodealliance/jco