TIL #146 – Using maturin through uv

Today I learned how to setup a Rust project that can be called from Python with PyO3 and maturin through uv. When you follow the PyO3 getting started guide to create a simple Rust project that can be called from Python, the instructions you get assume you'll use a global Python installation to create a virtual environment and to install maturin into it. You can use uv through maturin, but if your project also has a Rust binary, things may break. When you run a command like cargo run, cargo will see the dependency on PyO3 and it will then look for a Python installation. If you have no global Python installations — because you do everything through uv — or if your global installations aren't setup exactly like a vanilla, default installation, PyO3 might fail. The fix is simple. In .cargo/config.toml add the environment variable PYO3_PYTHON that points to the Python inside your virtual environment: # .cargo/config.toml [env] PYO3_PYTHON = { value = ".venv/bin/python", relative = true }…

Commenting on Bubbles has been removed. Why? If you want to talk about this post, write to the author, use the comments on their blog if it has them, or reply with a "RE:" post on your own blog. Suggestions? feedback@bubbles.town