Python Project Development (Lean)

Use this skill when

• creating Python CLIs or packages
• setting up pyproject.toml
• preparing build/publish workflows
• tightening packaging, linting, and test gates

Defaults

• Prefer uv for dependency and run workflows.
• Keep package layout src/<package_name>/.
• Use typed function signatures and explicit exit codes.
• Treat ruff + tests as baseline quality gates.

Core workflow

1. Choose project type: CLI, library, or hybrid.
2. Scaffold minimal pyproject.toml and package layout.
3. Implement entry point and core module.
4. Add tests and lint config.
5. Validate build/install locally.

Minimal commands

# Install project deps
uv sync

# Lint and format
uv run ruff check .
uv run ruff format .

# Test
uv run pytest

# Build artifacts
uv run python -m build

Constraints

• No hardcoded secrets/paths.
• Avoid heavy dependencies without clear payoff.
• Keep packaging metadata accurate and minimal.

References

• references/reference.md
• references/examples.md
• references/patterns.md
• references/stdlib_perf.md