python-packaging-patterns

What problem does it solve? Python projects often ship with inconsistent layouts, duplicated version strings, and fragile dependency specs that break installs and publishing. This Skill provides concrete patterns for structuring packages, configuring pyproject.toml, and managing dependencies so distribution works reliably. ## Core Features & Use Cases - Project Layout Guidance: Choose between src layout and flat layout with clear rationale for testability and import safety. - pyproject.toml Configuration: Set up build backends (hatchling, setuptools, flit, poetry-core), optional dependency groups, entry points, and tool configs for Ruff, Pytest, and Mypy. - Versioning & Publishing: Apply single-source versioning, CalVer for system packages, lockfile generation with uv or pip-tools, and PyPI publishing including trusted publishing via GitHub Actions. - Use Case: When starting a new Python library, use this Skill to scaffold a src-layout project with hatchling, dev dependency groups, and a console script entry point ready for editable install and PyPI release. ## Quick Start Set up a new Python package with a src layout, hatchling build backend, and dev dependencies configured in pyproject.toml.