scikit-build-core 0.1.0a0

PEP 517 builder for Scikit-Build

scikit-build-core

WARNING: Experimental. All configuration subject to change. Only scikit_build_core.build should be used (setuptools backend is experimental and likely to move to a separate package).

The following limitations are present compared to classic scikit-build:

• The minimum supported CMake is 3.15
• The minimum supported Python is 3.7
• Only the Ninja generator is supported on UNIX
• Only the MSVC generator (currently not tied to the current Python) is supported on Windows

Some of these limitations might be adjusted over time, based on user requirements & effort / maintainability.

This is very much a WIP, some missing features:

• The extensionlib integration is missing
• No hatchling plugin yet
• The docs are not written
• The logging system isn't ideal yet
• Dedicated entrypoints still need to be designed
• No support for other targets besides install
• C++17 is required for the test suite because it's more fun than C++11/14
• No support for caching between builds
• No editable mode support
• No extra wheel directories (like headers) supported yet
• Windows ARM support missing
• No Limited API / Stable ABI support yet, or pythonless tags

Features over classic Scikit-build:

• Better warnings and errors
• No warning about unused variables
• Automatically adds Ninja and/or CMake only as required
• Closer to vanilla setuptools in setuptools mode, doesn't interfere with config
• Powerful config system
• Automatic inclusion of site-packages in CMAKE_PREFIX_PATH
• FindPython is backported if running on CMake < 3.24 (included via hatchling in a submodule)

Currently, the recommended interface is the PEP 517 interface. There is also a setuptools-based interface that is being developed to provide a transition path for classic scikit-build.

Example

To use scikit-build-core, add it to your build-system.requires, and specify the scikit_build_core.build builder as your build-system.build-backend. You do not need to specify cmake or ninja; scikit-build-core will require them automatically if the system versions are not sufficient.

[build-system]
requires = ["scikit-build-core"]
build-backend = "scikit_build_core.build"

[project]
name = "scikit_build_simplest"
version = "0.0.1"

You can (and should) specify the rest of the entries in project, but these are the minimum to get started.

An example CMakeLists.txt:

cmake_minimum_required(VERSION 3.15...3.24)

project(${SKBUILD_PROJECT_NAME} LANGUAGES C VERSION ${SKBUILD_PROJECT_VERSION})

find_package(Python COMPONENTS Interpreter Development.Module)

Python_add_library(_module MODULE src/module.c WITH_SOABI)

install(TARGETS _module DESTINATION ${SKBUILD_PROJECT_NAME})
install(FILES src/simplest/__init__.py
        DESTINATION ${SKBUILD_PROJECT_NAME})

Scikit-build-core will backport FindPython from CMake 3.24 to older versions of Python, and will handle PyPy for you if you are building from PyPy. You will need to install everything you want into the full final path inside site-modules (so you will usually prefix everything by the package name).

Warning: FindPython does not report the correct SOABI for PyPy due to the SOABI being reported incorrectly. This will be fixed in the next release of PyPy. And PyPy doesn't support skipping the SOABI to avoid clashes with CPython. Pybind11's pybind11_add_module handles this correctly for you.

More examples are in the tests/packages.

Acknowledgements

Support for this work was provided by NSF cooperative agreement OAC-2209877.