UV+Neovim+Python LSPs

I use Neovim with the built-in LSP client, but I’m encountering an issue when working with multiple Python projects that each have their own virtual environments.

To ensure Neovim picks up the correct virtual environment, I need to cd into the project directory and manually activate the environment using source <venv>/bin/activate. This works fine when editing a single project.

However, if I want to open a different Python project during the same Neovim session, I must start a new instance of Neovim and repeat the activation process. Without doing this, the Python LSP does not use the appropriate environment for the second project.

There is an ongoing GitHub issue (#500) that discusses various solutions and workarounds for this problem.

Fortunately, ty, pyrefly and basedpyright support project-specific virtual environments: link for basedpyright.

To ensure basedpyright picks up the correct virtual environment, it is necessary to create a pyrightconfig.json file at the root of each project with the following structure:

{
  "venvPath": "<absolute-path-to-parent-directory-of-venv>",
  "venv": "<name-of-virtual-environment>"
}

venvPath is the directory containing all virtual environments, while venv refers to an individual virtual environment.

I wrote a small utility script called workon to help manage Python virtual environments more efficiently.

Python versions used for the environments are those installed via uv.

When executed, workon attempts to activate the appropriate virtual environment for the current project directory. If no associated virtual environment is found, it prompts the user to create a new one.

Then, it generates the pyrightconfig.json, ty.toml and pyrefly.toml files. I put them in global ~/.config/git/gitignore to avoid polluting the git history.

workon in action

Two projects, one with fastapi and another with django installed, both distinct virtual environments. Go-to-definition jumps to the project-specific virtual environments.

inside neovim

There is also plugin for neovim