Proposal: StarlingMonkey Playground for JS-in-Wasm Components

[iamrajiv]

I’m exploring how to improve the developer experience around WebAssembly components, specifically for JavaScript developers using StarlingMonkey and componentize-js. I’d like to propose a browser- or server-accessible playground that allows users to write JavaScript, compile it to a Wasm component, and execute it using StarlingMonkey.

Such a playground would:

• Allow JS developers to test and run JavaScript code as WebAssembly components without needing to set up a local toolchain.
• Demonstrate how StarlingMonkey integrates with WASI and the Component Model.
• Serve as an educational tool to visualize the WIT interface and component boundaries in real-time.

Proposed Features

• A simple UI for JS code input.
• Backend that compiles JS code into a component (via componentize-js or jco).
• Executes the component using Wasmtime + StarlingMonkey.
• Shows output from console.log, return values, or HTTP handlers.

[guest271314]

Should be possible. How far have you gotten?

[ajvincent]

I just found out about this project today, and I think yeah, this would be pretty nice to see. A JavaScript engine compiled to WASM and invoked from JavaScript: I actually have a couple uses for that.

[guest271314]

A JavaScript engine compiled to WASM and invoked from JavaScript:

Possible using qjs-wasi.wasm.

And/or javy.

[guest271314]

@ajvincent See https://github.com/guest271314/javy-browser-host and https://github.com/guest271314/native-messaging-webassembly/blob/main/nm_javy_node_wasi.js.