Pyo3 - Langgraph Prove of Concept

This project is a proof of concept that you can use Langgraph just as easy as in Python, but in Rust instead, with the power of Pyo3.

Features

• A bare minimum chat interface built with inquire.
• A bare minimum graph that accepts user message and send it to Ollama.
• All chat history are perserved through one session.

How is It Done?

Go read the code :). JK, pyo3 is doing the heavy-lifting here. It allows you to use any Python packages just like in Python. Most of the time you are just translating Python code into Rust with 1:1 ratio, or 1:2 because it’s a little bit more verbose in Rust.

The streaming is a little bit tricky thought. In Python, you would do:

stream = streamer()
for chunk in stream:
print(chunk)

But in Rust, you need to tweak it just a little bit.

let stream = streamer.call0()?;
while let Ok(chunk) = stream.getattr(py, "__next__")?.call0(py) {
println!("{chunk}");
}

See? Really just a small tweak, but you are writing Rust now! Hooray!

Run It Yourself!

Requirements

• Rust >= 1.92
• Python >= 3.13

Setup

make init

Run

make dev

Showcases

Contribution

Feel free to open tickets and PRs! Do whatever you want with this knowledge. I mean it’s just a POC, and a showcase of the power of Rust community :)