python-poetry / poetry-core

Poetry PEP 517 Build Backend & Core Utilities

Poetry Core

A PEP 517 build backend implementation developed for Poetry. This project is intended to be a lightweight, fully compliant, self-contained package allowing PEP 517-compatible build frontends to build Poetry-managed projects.

Usage

In most cases, the usage of this package is transparent to the end-user as it is either used by Poetry itself or a PEP 517 frontend (eg: pip).

In order to enable the use of poetry-core as your build backend, the following snippet must be present in your project's pyproject.toml file.

[build-system]
requires = ["poetry-core"]
build-backend = "poetry.core.masonry.api"

Once this is present, a PEP 517 frontend like pip can build and install your project from source without the need for Poetry or any of its dependencies (besides poetry-core).

# install to current environment
pip install /path/to/poetry/managed/project

# build a wheel package
pip wheel /path/to/poetry/managed/project

Why is this required?

Prior to the release of version 1.1.0, Poetry was a project management tool that included a PEP 517 build backend. This was inefficient and time consuming when a PEP 517 build was required. For example, both pip and tox (with isolated builds) would install Poetry and all dependencies it required. Most of these dependencies are not required when the objective is to simply build either a source or binary distribution of your project.

In order to improve the above situation, poetry-core was created. Shared functionality pertaining to PEP 517 build backends, including reading pyproject.toml and building wheel/sdist, were implemented in this package. This makes PEP 517 builds extremely fast for Poetry-managed packages.