Modern Python

Before changing a project, read its instructions and current configuration, preserve supported Python versions, and run installed CLI help. Do not replace a working toolchain unless the user requests migration and the replacement reaches validation parity.

Route

• Standalone script with dependencies: read PEP 723 scripts.
• New project or package: read pyproject, Ruff config, and testing.
• Existing project migration: read migration checklist before editing.
• uv command detail: read uv commands.
• Security tooling: read security setup, Dependabot, and prek only when requested or already used.

Defaults for new work

• Manage dependencies with uv add, uv remove, and uv sync; run commands with uv run.
• Use dependency groups for development tools.
• Use Ruff for lint and format, ty for type checks, and pytest for tests unless project constraints require otherwise.
• Prefer uv_build for ordinary new packages.
• Never manually activate or manage a virtualenv.