uv — Extremely Fast Python Package and Project Manager

Introduction

uv is a revolutionary Python package and project manager that replaces an entire stack of tools with a single, blazing-fast binary. Built in Rust by Astral (the creators of Ruff), uv is 10-100x faster than pip for package installation and provides a unified workflow for managing Python versions, virtual environments, dependencies, and project builds.

With over 83,000 GitHub stars in just over a year, uv is the fastest-growing tool in the Python ecosystem. It has rapidly become the recommended way to manage Python projects, endorsed by major frameworks and organizations.

What uv Does

uv replaces six separate tools in the Python ecosystem: pip (package installer), pip-tools (dependency resolver), virtualenv (environment creator), pyenv (Python version manager), pipx (tool installer), and poetry/PDM (project manager). One tool, one binary, dramatically faster.

Architecture Overview

[uv (single Rust binary)]
        |
+-------+-------+-------+
|       |       |       |
[Project]  [Package]  [Python]
Management  Install    Version
uv init    uv add     uv python
uv run     uv pip     install
uv build   uv lock    uv python
uv publish             list
        |
[Replaces]
pip + pip-tools + virtualenv
+ pyenv + pipx + poetry
        |
[Performance]
10-100x faster than pip
Global cache with hard links
Parallel downloads

Self-Hosting & Configuration

# pyproject.toml — uv project configuration
[project]
name = "my-app"
version = "0.1.0"
requires-python = ">= 3.11"
dependencies = [
    "fastapi>=0.115",
    "sqlalchemy>=2.0",
    "httpx>=0.27",
]

[project.scripts]
serve = "my_app.main:run"

[tool.uv]
dev-dependencies = [
    "pytest>=8.0",
    "ruff>=0.8",
    "mypy>=1.13",
]

# Common uv workflows
uv init my-app             # Create new project
uv add fastapi              # Add dependency
uv add --dev pytest         # Add dev dependency
uv lock                     # Generate lockfile
uv sync                     # Install from lockfile
uv run pytest               # Run in virtual env
uv run python main.py       # Run scripts
uv build                    # Build package
uv publish                  # Publish to PyPI
uv tool install ruff        # Install CLI tool globally
uv python install 3.12      # Install Python version

Key Features

• 10-100x Faster — Rust-powered package resolution and installation
• All-in-One — replaces pip, virtualenv, pyenv, pipx, and poetry
• Universal Lockfile — cross-platform reproducible dependency resolution
• Python Version Management — install and switch Python versions
• Global Cache — shared cache with hard links for zero-cost duplicates
• pip Compatible — drop-in replacement for pip commands (uv pip install)
• Script Support — inline script metadata for single-file dependencies
• Cross-Platform — works on Linux, macOS, and Windows

Comparison with Similar Tools

FAQ

Q: Can I replace pip with uv in existing projects? A: Yes. Use "uv pip install" as a drop-in replacement for pip. For full project management, run "uv init" in an existing directory to generate a pyproject.toml and migrate.

Q: Does uv work with existing requirements.txt files? A: Yes. "uv pip install -r requirements.txt" works exactly like pip. You can also migrate to uv lockfiles with "uv add" commands.

Q: How does uv achieve such speed? A: uv is written in Rust with parallel downloads, a global package cache with hard-link deduplication, and an optimized dependency resolver. It avoids the overhead of Python startup and pip internals.

Q: Is uv stable enough for production? A: Yes. uv follows semantic versioning and is used by major Python projects. Astral (backed by significant VC funding) is committed to long-term maintenance.

Sources

• GitHub: https://github.com/astral-sh/uv
• Documentation: https://docs.astral.sh/uv
• Website: https://astral.sh
• Created by Charlie Marsh and Astral team
• License: MIT / Apache-2.0