uv: Package, Project, Dependency, Environment

Table of Contents

Finally we have a really good package, project, dependency and environment management tool for Python.

uv is a Python package, dependency and environment management tool. It is a good replacement for pip, pip-tools, pipx, poetry, pyenv, twine, virtualenv

Coming from a rust ecosystem, uv is inspired by cargo and rustup. There are lots of similarities between cargo and uv. In the traditional Python ecosystem, there are too many tools to manage packages, dependencies and environments. uv tries to unify all these tools into one.

Advantages:

  • Speed: Resolves dependencies really fast
  • Simplicity: Virtual Environment and package management is simplified
  • Compatibility: Works with pip and pip-tools
  • Modern: Built using rust for performance and stability

Installation

Simplest way to install uv on a mac is to use brew:

% brew install uv
% uv --version

Let’s create a sample virtual environment and install some packages.

% uv venv ./myenv --python 3.13
% source ./myenv/bin/activate
% uv pip install -r requirements.txt

To list of all available python that uv can find, run the following command:

% uv list python

Dependency management

Due to the fact that there are so many packages in the Python ecosystem, it is very hard to manage dependencies in a project. In fact, this is true with any programming language. In rust ecosystem, cargo is the tool that manages dependencies.

One mechanishm uv uses is to let you generate a lock file that can be used in any machine, any environment to install packages with the exact same dependencies, unless there are OS specific dependencies that needs to be reflected.

Let’s start with a simple project management case and create a new project

% uv init foobar
% cd foobar
% ls -a
pyproject.toml README.md main.py
.git/   .python-version/  .venv/

Note: these are the bare minimum project files

Now let’s add some packages to the project and lock the dependencies

% uv add requests ruff
% uv run ruff check
% uv lock

Now if you look at the file uv.lock, you will see all the dependencies and their versions.

% cat uv.lock | more

Now let’s run files, add some files and run the project

% uv run main.py
% echo 'import requests; print(requests.get("http://google.com"))' > example.py
% uv run example.py

To resolve and audit the dependencies, run the following command:

% uv sync

Now let’s go back to the Project and add some more dependencies

% uv add numpy pandas openai
% uv lock