# Astral Uv

> Fast Python package and project management using Astral's uv. Use when installing packages, managing virtual environments, running Python scripts, or initializing Python projects. Triggers on: pyproject.toml, requirements.txt, Python dependency discussions, virtual environment setup.

- Skill: `majiayu000/astral-uv` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds add majiayu000/astral-uv`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/astral-uv/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- License: MIT
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/astral-uv

---


# Astral UV

UV is an extremely fast Python package installer and resolver written in Rust.

## Quick Reference

| Task | Command |
|------|---------|
| Create venv | `uv venv` |
| Install package | `uv pip install <pkg>` |
| Add dependency | `uv add <pkg>` |
| Run script | `uv run <script.py>` |
| Sync dependencies | `uv sync` |
| Init project | `uv init` |

## Project Management

Initialize a new project:
```bash
uv init my-project
cd my-project
```

Add dependencies (updates pyproject.toml automatically):
```bash
uv add requests httpx
uv add --dev pytest ruff
```

Sync environment with lockfile:
```bash
uv sync
```

## Running Code

Run scripts without manual venv activation:
```bash
uv run python script.py
uv run pytest
uv run ruff check .
```

Run with inline dependencies:
```bash
uv run --with requests script.py
```

## Virtual Environments

```bash
uv venv                    # Create .venv
uv venv --python 3.12      # Specific Python version
```

## pip Interface

Drop-in pip replacement (10-100x faster):
```bash
uv pip install requests
uv pip install -r requirements.txt
uv pip compile requirements.in -o requirements.txt
```

## Python Version Management

```bash
uv python install 3.12     # Install Python version
uv python list             # Show available versions
uv python pin 3.12         # Pin version for project
```

## Best Practices

1. Prefer `uv add` over `uv pip install` for project dependencies
2. Use `uv run` instead of activating venvs manually
3. Commit `uv.lock` to version control
4. Use `uv sync --frozen` in CI for reproducible builds
5. Add dev dependencies with `uv add --dev`