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

41•tuananh•8mo ago

Comments

digdugdirk•8mo ago

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.

ushakov•8mo ago

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

check it out: https://e2b.dev

benno128•8mo ago

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

aitchnyu•8mo ago

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

benno128•8mo ago

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.

apitman•8mo ago

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

someguy101010•8mo ago

https://github.com/r33drichards/mcp-js mcp for running javascript locally and safely using v8

sudb•8mo ago

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.

apignotti•8mo ago

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.

TZubiri•8mo ago

Sounds cool. We already have browser use though!

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

nilslice•8mo ago

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

TZubiri•8mo ago

Or just use Chatgpt.

ubermonkey•8mo ago

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

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