For years, setting up Python meant juggling pip, virtualenv, pyenv and a requirements.txt that never quite matched production. uv, from Astral, the team behind the Ruff linter, combines those jobs in one very fast tool written in Rust. It has quickly become a popular default for new Python projects.
One tool instead of four
- pip
uv add,uv sync(oruv pip install)- virtualenv / venv
- Created automatically by
uv run - pyenv
uv python install- pipx
uvx
Install uv
# macOS and Linux
curl -LsSf https://astral.sh/uv/install.sh | sh
# or with Homebrew
brew install uvInstall and pin a Python version
uv python install 3.14 # downloads a managed Python build
uv python list # shows installed and available versionsStart a project
uv init sales-report
cd sales-report
uv add pandas openpyxl duckdb # adds to pyproject.toml and updates uv.lock
uv add --dev ruff pytest # development-only dependenciesThis creates a pyproject.toml describing your dependencies and a uv.lock file recording exact versions. Commit both to Git so everyone, including your server, runs the same versions.
Run code without activating anything
uv run python report.py # creates or updates .venv automatically, then runs
uv run pytest
uv sync # install exactly what uv.lock specifiesSingle-file scripts with inline dependencies
For a quick automation, you can declare dependencies at the top of the script itself, following the inline script metadata standard (PEP 723).
# /// script
# requires-python = ">=3.12"
# dependencies = ["pandas", "openpyxl"]
# ///
import pandas as pd
df = pd.read_excel("sales.xlsx")
print(df.groupby("region")["amount"].sum())uv run report.py # uv installs pandas and openpyxl in an isolated environment firstRun tools without installing them
uvx ruff check . # lint your code
uvx ruff format . # format itComing from requirements.txt
uv add -r requirements.txt # import an existing list into a project
uv export --format requirements-txt > requirements.txt # produce one for other toolsCheck your understanding
1/3Which two files should you commit to Git in a uv project?
The lock file records exact versions so everyone runs the same ones; .venv is recreated.
2/3What does uv run python report.py do first?
There is nothing to activate.
3/3How do you run Ruff without installing it in your project?
uvx runs tools in a temporary, isolated environment.
You got 0 out of 3.
Put uv to work: automate a weekly report, or see what's new in Python 3.15 (uv python install 3.15).
Alessandro Ecclesie AgazziWritten by Alessandro Ecclesie Agazzi, analytics engineer in London. Updated 30 September 2026. About me