Implement `node:wasi`

[littledivy]

std/wasi is being deprecated https://github.com/denoland/deno_std/pull/3732 and it would be nice to offer an alternative i.e node:wasi before it's removal.

Some ideas on perfomance:

• https://github.com/littledivy/fastwasi
• https://github.com/denoland/deno_core/pull/289

[rracariu]

Interesting, would this go further and add implementation for WASI preview2? How about supporting wasm32-wasi-threads?

[terrablue]

Are there any plans to implement this? I'm using ruby.wasm in my software, which relies on node:wasi, which means that users who wish to write ruby backend code can't use deno.

[mdekstrand]

I would love to see WASI support for Deno.

In the mean time, perhaps it should be removed from the docs until this is implemented? I expected it would work from seeing it in the docs, and was surprised that the module cannot even be imported.

[glebbash]

Existing "alternatives":

• lib for running WASI preview1 @wasmer/wasi from wasmer-js but it only provides an in-memory file system and Wasmer team seems to be focusing on WASIX and integration with Wasmer Cloud.

• an ongoing effort in VSCode to support WASI. @dbaeumer's approach with Web Workers, SharedArrayBuffer and Atomics sounds like a good way of making an async runtime (at the cost of creating a Web Worker).

• @bytecodealliance/preview2-shim from jco but they only have preview2 support.

---

It would be very nice to have a cross-platform (Node.js/Deno/browsers) WASI runtime.

Here is a WASI preview1 shim (for Node & Deno) I wrote that can be used as an inspiration for anyone interested in writing a full lib.

[terrablue]

@glebbash cool, these all sound interesting.

My issue is that I rely on the ruby.wasm project to run Ruby on the server, and that relies on node:wasi. I doubt it would be easy to convince the author of ruby.wasm to use another library.