Where does the bug appear (feature/product)? Cursor IDE Describe the Bug Extremely poor performance navigating Python codebase Steps to Reproduce Upgrade to the latest version of Cursor. Try to navigate a Python codebase which already existed, such as finding references to a class method Performa…

We don’t have a hard limit on the # of files; it will depend on the resources of your computer. The implementation in the new extension is different, so having excluded folders will help with performance.

Could you provide any info about how to debug it? Logs to look for? How to know which folders are causing the problem? TBH, I would prefer to revert, if possible.

The “Cursor - Pyright” and “basedpyright” output consoles would contain logs for the Python language server.

Even after reducing it to 800 files it’s still slow: [Info - 12:30:07 PM] Found 837 source files And that’s after ignoring my .venv folder, which doesn’t feel super great as I’d like to freely navigate between project source and dependencies

+1. Me and my team having same issue post update. Unusable unfortunately. We have a python mono-repo & pretty sure any enterprise level company writing python code outside of a pet project will hit this if the performance is bad on 800 files. Especially because my dev machine is pretty beefy… @ravi…

This new anysphere Python plugin also has odd behavior for code completion, unreachable code parsing, and handling custom text color settings. In a DRF view anytime you call “get_object()” it is saying all the code beneath it is unreachable. Does not behave like the MS python extension. I am also i…

The option installing ty + pyrefly did not work for us. These tools incorrectly report issues for things that pylance supports. It would be very helpful to have an answer to @Ryan_St_Pierre ‘s questions. It has been multiple weeks with no clarity. So to re-hash A) Anysphere is not ready for usage …

Hi Daniel, I’m on the Pyrefly team. Do you know which behaviors/performance you’d like to see from Pylance?

The main thing for us in particular would be native support for Pydantic. Pydantic I feel like has become quite popular, and pylance correctly supports the intended patterns Pydantic enables. A very simple example is before validators. e.g.: from pydantic import BaseModel, field_validator class …

Poor performance for Python code navigation after upgrade

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Benedetto_Grillone (Benedetto Grillone) September 17, 2025, 7:58am 14

Was experiencing the same issue. Uninstalling the Python extension and installing pyrefly and ty as suggested here Cursor pyright slooooooow - #7 by ravirahman fixed it for me

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Poor performance for Python code navigation after upgrade

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