alt.hn

5/17/2025 at 1:49:06 PM

Show HN: A MCP server to evaluate Python code in WASM VM using RustPython

 https://github.com/tuananh/hyper-mcp/tree/main/examples/plugins/eval-py

by tuananh

5/19/2025 at 9:25:58 PM

Is there a list of these "code sandboxes" floating around somewhere? It seems like it's going to be more and more important with LLMs playing more of a factor in development moving forward.

by digdugdirk

5/20/2025 at 1:10:54 PM

I know of https://modal.com/, which I believe is used by Codegen and Cognition.

Anecdotally-speaking, I hear that many companies in the LLM agent space roll their own sandbox solutions - I've heard of both Firecracker- and Kubernetes-based implementations.

by sudb

5/20/2025 at 12:17:24 AM

I've got one that uses WebAssembly to run Python, Ruby, C/C++, JS: https://runno.dev/articles/sandbox/

by benno128

5/20/2025 at 7:51:12 PM

You should repost that article on HN. WASI in the browser is awesome and I would love to see some discussion about it.

by apitman

5/20/2025 at 6:17:32 AM

Is there a better way to sandbox Python other than using a webassembly build?

by aitchnyu

5/20/2025 at 9:00:56 AM

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.

by benno128

5/19/2025 at 10:50:20 PM

i work on E2B, we are open-source sandbox runtime used by Perplexity, Manus, Hugging Face among others.

check it out: https://e2b.dev

by ushakov

5/19/2025 at 10:08:28 PM

I cannot be the only GenX nerd who reads that and thinks "Master Control Program" from Tron.

by ubermonkey

5/19/2025 at 9:30:09 PM

Does anyone know if there is work on the idea of letting MCP-like "servers" run on the client-side? I.e. in the same browser tab as ChatGPT or Claude?

This specific example would make much more sense if it could run sandboxed client-side.

by apignotti

5/19/2025 at 10:15:24 PM

all of the servers deployed to mcp.run[0] are Wasm modules, and can run client side. they run in our cloud too, but you could use mcpx to pull them locally instead.

you can also get the raw wasm via our API and run them anywhere you can run Extism[1], the open source wasm runtime & framework that underpins it all. (Including this hyper-mcp project!)

[0]: https://mcp.run [1]: https://github.com/extism/extism

by nilslice

5/19/2025 at 9:57:11 PM

Sounds cool. We already have browser use though!

You can also roll your own with selenium and c vision or selectors.

by TZubiri

5/19/2025 at 9:56:37 PM

Or just use Chatgpt.

by TZubiri