Feature Request: Consider migrating Python language support to **pyrefly** for better performance and consistency

[kv9898]

Hi Positron team,

Thank you for all your hard work to bring this amazing product!

I wanted to ask whether there are any plans to migrate Positron’s Python language support base from the current MS Python extension + Pyright setup to pyrefly.

The existing setup works well overall, but it currently misses some Pylance-specific functionality (such as richer type inference and completions). Moreover, since the current extension is implemented in Python, it can become less ideal for handling very large or complex codebases.

By contrast, pyrefly offers some appealing technical advantages:

It’s Rust-based, aligning naturally with Positron’s Ark backend (also Rust), enabling more consistent and performant backend logic.

It promises improved scalability and responsiveness for large projects.

It’s MIT licensed, so there should be no licensing concerns.

That said, I completely understand that such a transition would represent a significant amount of engineering work — and as someone who has contributed to the Ark project, I know firsthand how complex and far-reaching these integrations can be. I’m also aware that pyrefly is still in a fairly early (alpha) stage, so this wouldn’t be an immediate or short-term goal.

Still, I wanted to raise this as a longer-term consideration, as the alignment between a Rust-based backend and pyrefly could eventually provide a more cohesive and high-performance experience for Python development in Positron.

Thanks for all your work on Positron — it’s been great to see the pace of development and the technical direction you’re taking!

[juliasilge]

We are actually just starting some work on evaluating our Python LSP support and integration, such as in #10303. Definitely on our minds right now! Look for more details soon.