# Python Dependency

> Python dependency management preferences using uv. Use when adding Python dependencies, creating Python projects, setting up virtual environments, writing standalone scripts with external packages, or when pip, requirements.txt, venv, virtualenv, pyproject.toml, or uv is mentioned. Ensures uv is used instead of pip/venv.

- Skill: `rewse/python-dependency` (Agent Skill)
- Install (CLI): `npx skillmds@latest add rewse/python-dependency`
- Raw SKILL.md: https://api.skillmd.com/api/skills/rewse/python-dependency/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: rewse (https://skillmd.com/u/rewse)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/rewse/python-dependency

---


# Python Dependency Management

**Do**

- Use inline script metadata with `uv run` for standalone scripts
- Use `pyproject.toml` with `uv` for multi-file projects

**Don't**

- Use `pip install` or `requirements.txt`
- Use `venv` or `virtualenv` directly

### Inline Script Dependencies (Recommended)

For Python scripts that need external dependencies, use inline script metadata with `uv run`. This approach ensures scripts are self-contained and dependencies are automatically managed.

```python
#!/usr/bin/env -S uv run
# /// script
# dependencies = [
#   "pyyaml",
#   "requests",
# ]
# ///

import yaml
import requests

# Your script code here
```

#### Usage

```bash
uv run script.py
# or with shebang
./script.py
```

### Project-based Dependencies

For larger projects with multiple scripts and modules, use `pyproject.toml` to manage dependencies.

```bash
cd your-project
uv init                  # Create pyproject.toml
uv add pyyaml requests   # Add dependencies
uv run python script.py  # Run scripts
```

```toml
[project.scripts]
my-command = "my_package.cli:main"

[build-system]
build-backend = "uv_build"

[tool.uv.build-backend]
module-root = "src"
```

#### When to Use

- Projects with multiple Python files
- Shared dependencies across multiple scripts
- Projects requiring development dependencies (testing, linting, etc.)

#### Testing

Execute tests using `uv run` with `PYTHONPATH=src`. The `src` layout requires this so Python can resolve modules under `src/` during test execution.

Example: `PYTHONPATH=src uv run pytest tests/test_foo.py`