This example demonstrates using Porringer to bootstrap a complete Python development environment from scratch — the same chain a developer would follow manually.

The manifest executes in phased order:

1. runtimes.python → installs Python 3.14 via pim (Windows) or pyenv (macOS / Linux). The resolved interpreter path is propagated to all downstream phases.
2. packages.python → installs pipx into the current Python environment via pip or uv.
3. tools.python → installs pdm as an isolated CLI tool via pipx. The pipx backend is deferred at preview time — it becomes available only after Phase 2 installs it.
4. post_sync → runs pdm install in the manifest directory, creating the project virtualenv and installing all dependencies from pyproject.toml.

runtimes.python  ─►  pim / pyenv   ─►  Python 3.14
packages.python  ─►  pip / uv      ─►  pipx
tools.python     ─►  pipx          ─►  pdm          (deferred resolution)
post_sync        ─►  pdm install                    (project sync)

porringer sync --path examples/python-bootstrap --dry-run

porringer sync --path examples/python-bootstrap

porringer sync --path examples/python-bootstrap --yes

Porringer's execution engine splits PACKAGE-type actions into sub-phases:

• Phase 1 (Runtime): Runtime providers (pim / pyenv) run first. The resolved interpreter is forwarded to all RuntimeConsumer plugins so that subsequent pip / uv commands target the correct Python.
• Phase 2a (Package): Regular package installs (pip / uv). This is where pipx gets installed.
• Phase 2b (Tool): After Phase 2a the engine re-discovers available plugins. Pipx is now on PATH, so the tools.python section resolves to the pipx backend and pdm is installed.
• Phase 3 (Project Sync): Project-environment plugins (pdm, uv, poetry) run their native sync / install command.
• Phase 4 (Post-sync): Arbitrary shell commands execute in the manifest directory.

If a tool backend is not available at preview time (e.g. pipx is not yet installed), the action is created with a deferred installer. Resolution happens just before Phase 2b, after packages have been installed.