python-package-management

## Quick Reference

| uv Command | Purpose |
|------------|---------|
| `uv init my-project` | Create new project |
| `uv add <package>` | Add dependency |
| `uv add --dev <package>` | Add dev dependency |
| `uv sync` | Install all dependencies |
| `uv run <command>` | Run in virtual env |
| `uv lock --upgrade` | Update all deps |
| `uv python install 3.13` | Install Python version |

| Tool | Command | Speed |
|------|---------|-------|
| uv | `uv add requests` | 10-100x faster |
| pip | `pip install requests` | Baseline |

| ruff Command | Purpose |
|--------------|---------|
| `ruff check .` | Lint code |
| `ruff check --fix .` | Auto-fix issues |
| `ruff format .` | Format code |

| Project Layout | Recommended |
|----------------|-------------|
| src layout | `src/my_package/` |
| Tests | `tests/` |
| Config | `pyproject.toml` |

## When to Use This Skill

Use for **project setup and dependencies**:
- Starting new Python projects
- Setting up uv for fast package management
- Configuring pyproject.toml
- Setting up linting with ruff
- Publishing packages to PyPI

**Related skills:**
- For CI/CD: see `python-github-actions`
- For testing: see `python-testing`
- For type hints config: see `python-type-hints`

---

# Python Package Management (2025)

## Overview

Modern Python package management centers around `uv` (the fast Rust-based tool), `pip`, and `pyproject.toml`. This guide covers best practices for dependency management, virtual environments, and project configuration.

## uv - The Modern Package Manager

### Why uv?

- **10-100x faster** than pip (written in Rust)
- Replaces pip, pip-tools, pipx, poetry, pyenv, virtualenv
- Automatic virtual environment management
- Lockfile support for reproducibility
- ~200x faster venv creation

### Installation

```bash
# macOS/Linux
curl -LsSf https://astral.sh/uv/install.sh | sh

# Windows (PowerShell)
irm https://astral.sh/uv/install.ps1 | iex

# pip (works everywhere)
pip install uv

# Homebrew
brew install uv
```