reference-types VS webcontainer-core

> It could be an interesting use case for WASM if the problem of passing data into the WASM VM cheaply (perhaps by reference) can be solved.

WASM Reference Types should hopefully solve this. The WASM working group seems to have some good momentum - so I'm hopeful this (or a similar replacement spec) will land sooner rather than later.

https://github.com/WebAssembly/reference-types/blob/master/p...

AFAIK GC is irrelevant for "direct DOM access", you would rather want to hop into the following rabbit hole:

- reference types: https://github.com/WebAssembly/reference-types/blob/master/p...

- interface types (inactive): https://github.com/WebAssembly/interface-types/blob/main/pro...

- component model: https://github.com/WebAssembly/component-model

If this looks like a mess, that's because it is. Compared to that, the current solution to go through a Javascript shim doesn't look too bad IMHO.

[1]: https://github.com/WebAssembly/proposals

A glance of the overview and spec seems to indicate that WASM will provide some primitive data types, and any GC language can build their implementation on top of it. As I understand it, it's heavily based on Reference Types[3], which allows acting on host-provided types, and is already considered part of the spec [4]. It doesn't remove the need for the 5 different runtimes to have their own GC, but it lowers the bulk that the runtimes need to carry around, and offloads some of that onto the WASM runtime instead.

[3]: https://github.com/WebAssembly/reference-types/blob/master/p...

They've talked about interface types, and added reference types, which is a stepping stone toward the GC extension proposal, which would be a stepping stone toward manipulating the DOM from the WebAssembly side, but their official roadmap page is more short-term.

Nope, WASM reference types, it has nothing to do with .NET type system.

> And there's been talk of exposing the JS GC to wasm for a few years. Hopefully when that stuff lands, it'll get easier to marshal objects across the gap.

You don't need a Wasm GC to do this. If you only need js objects to pass on to, say, the host's function or check is null or not, then reference types that are opaque external references: https://github.com/WebAssembly/reference-types/blob/master/p...

You can even do many more things if you export `Reflect` to WebAssembly: https://github.com/AssemblyScript/assemblyscript/blob/main/t...

Reference Types are available almost everywhere already (In Safari will be available after 15.0): https://webassembly.org/roadmap

Re: GC -- yes, indeed, the whole business with safepoints arose from the need to support Wasm reference types as a backend for Wasmtime or Firefox. No safepoints are needed for Rust (or other C-like) code.

Reference Types,

How does it work? There is no backend whatsoever. The API Security Academy leverages WebContainers, a new technology that allows running full-blown node instances directly in the browser. Each WebContainer contains a live GraphQL application, so you'll not only understand why a vulnerability is risky, but also how to exploit it and, most importantly, how to fix it.

StackBlitz made the claim "... run Node.js, entirely inside your browser" #658, then had to revise it's claim to "We currently do not expose a way to use WebContainer outside of StackBlitz.com,".

> Wasm though seems like the likely general heir, and will have many different offerings for how to do that (Deno being one!).

I was recently blown away by some ideas that StackBlitz [0] apply based on WebContainers. The idea of a "server in the browser", they allow you to run Node-based environment like that via Wasm.

[0] https://stackblitz.com/

[1] https://webcontainers.io/

See https://webcontainers.io.

This very simple fact is well known flaw, which was already often criticized and asked for solutions by users. It doesn't only affect this kind of very exotic bootstrap applications but also significantly limits rusts usefulness in many other areas. Pure browser based scientific code documentation and example notebooks (e.g. jupyterLite) and sandboxed CI and IDE solutions (e.g. web containers) as available for many other languages are simply not available for rust because of this very fundamental issue.

Looks like they plan to open it. From the FAQ section of README (https://github.com/stackblitz/webcontainer-core#faqs):

> Is there a developer API?

I'm skeptical about stackblitz claims. The last time I checked that is closed source code https://github.com/stackblitz/webcontainer-core/issues/658.

StackBlitz claimed https://blog.stackblitz.com/posts/introducing-webcontainers/ to have implemented Node.js in the browser, though I have not observed any evidence of that being true and correct https://github.com/stackblitz/webcontainer-core/issues/658.

The other honorable mention is StackBlitz, a web-based web editor for making containers that run Javascript applications. Interestingly, StackBlitz is championing WebContainers, a technology that allows developers to start NodeJS servers within the browser. The downside is, this technology only works with Javascript-based projects (NodeJS, NextJS, etc). I include it here because WebContainers could easily be extended to support other languages via WASM, like Ruby. I’ll also add in Buildah, a tool for building OCI images. I won’t say much about this tool because it’s designed for building images; you still need another service, like Podman, to actually create the containers.