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benno128

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Yeah for sure: run it inside a virtual machine, or do some sort of docker magic.

You kind of need to pretend you are a whole computer for a programming language to be happy. There's built in assumptions they're running on a "real" computer. They assume they've got full access to network and disk. Installing packages often requires compiling C extensions, or running native binaries. All that stuff means the best way to sandbox is to virtualise a whole computer.

It's fun to do it with WebAssembly though, you get a lot of guarantees and it's quite light weight.

Thanks! Yeah I'm very aware of Pyodide and interested in adopting some of their techniques.

A big difference between my approach and their approach is that Runno is generic across programming languages. Pyodide only works for Python (and can only work for Python).

Big interesting development in this space is the announcement of Endor at WASM IO which I'd like to try out: https://endor.dev/

Working on Runno (https://runno.dev/) as a side project. It's a tool for running code in the browser for educational use.

[Edit]: I wrote a re-introduction to Runno: The WebComponent for Code over the weekend (https://runno.dev/articles/web-component/)

I've been playing around with turning it into a sandbox for running code in Python (https://runno.dev/articles/sandbox-python/). This would allow you to safely execute AI generated code.

Generally thinking about more ways to run code in sandbox environments, as I think this will become more important as we are generating a lot of "untrusted" code using Gen AI.

Really impressed by the depth and breadth of this project, well done!

A particularly interesting part is the socket layer inside the browser. Other people solving this problem have previously used a proxy to a server that does the real socket implementation. This means you can't have a "browser-only" solution.

The author has solved this (for HTTP/S only) by proxying HTTP requests and then re-creating them as fetch requests (details here: https://github.com/ktock/container2wasm/tree/main/examples/n...). I'm very interested in using this approach for my own project Runno (https://runno.dev).

Snapshot Preview 1 is the standard all tools are building to right now. The specification is available here: https://github.com/WebAssembly/WASI/blob/main/legacy/preview...

It's pretty unreadable though!

Preview 2 looks like it will be a big change, and is just being finalised at the moment. I'd expect that when preview 2 is available there will be an improvement in the quality of documentation. I'm not sure how long it will take after release for tools to start switching to it. I'd expect Preview 1 will still be the main target at least for the rest of this year.

I wouldn't put it in prod, but it would be possible. You'd need a JS binding layer that dealt with the output and wrote it to the page, but it could be minimal.

There are other projects that are targeted more at this kind of thing if you want dynamic access to the DOM from Web Assembly (sorry I don't know them off the top of my head).

Is this on the blog post, or are you trying it out yourself?

If it's on the blog post, it sounds like your browser doesn't support `SharedArrayBuffer` (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...) or you've disabled Cross Origin Isolation somehow. It might be because you have an old browser (there was a period where it was disabled) or you have disabled Cross Origin Isolation yourself (maybe a security setting?).

This is just plain wrong. Web Components work in every browser that matters. They are standard DOM elements and can be written in plain HTML server-side or via legacy front-end libraries.

I'm using web components in production to help interoperability between 2012 era Handlebars/jQuery/Backbone and modern tools like React and Prosemirror.

I think framing it this way can lead to real gripes with the interface. Web Components are a great way to build individual components that can be reused across an app, website, or shared as part of a library. They are like helper functions for HTML.

They don't work as well for building apps, sure you can do it, but tools like React/Vue/Svelte are much better at building a whole app experience. Particularly when you consider meta-frameworks and the ecosystem around them.

I’ve been using lit in side projects (e.g. runno.dev) and really enjoyed it. Just like any framework it can be a bit confusing learning the primitives but I’ve found it as productive as React, Vue or Svelte.

The thing I like most about lit is that it embraces web standards. Sometimes that means the ergonomics are a bit strange. But it also means it gets performance benefits, and interoperability bonuses. Plus it feels like you’re learning something about the underlying platform while you’re using it.

The best example is that it uses reactive data binding via attributes for passing data down the tree, and native DOM events for passing data up the tree. That allows you all the same safety that a framework like React offers, but also means your component can be used by any other framework, or by vanilla JS (because they all support the DOM).