Variables

Variables that are set by py-build-cmake

Below is a list of the CMake variables and environment variables that are set by py-build-cmake during the build process.

Variable	Description	Type
PY_BUILD_CMAKE_VERSION	The full version of py-build-cmake itself. This variable can be used to determine whether the package is being built by py-build-cmake or not.	CMake, Environment
PY_BUILD_CMAKE_PROJECT_NAME	The normalized name of the package being built ([project.name] in pyproject.toml). This name matches the eventual name of the Wheel file, and will be used for the distinfo directory inside of the Wheel.	CMake, Environment
PY_BUILD_CMAKE_PROJECT_VERSION	The full version of the package being built.	CMake, Environment
PY_BUILD_CMAKE_IMPORT_NAME	The import name of the top-level module or package of your project ([tool.py-build-cmake.module.name] in pyproject.toml). This can be used as the destination folder to install Python extension modules into.	CMake, Environment
PY_BUILD_CMAKE_BINARY_DIR	The CMake binary directory for the current build (note that there could be multiple build directories for a single package).	Environment
PY_BUILD_CMAKE_INSTALL_PREFIX	The CMake installation directory. Files that should be included in the Wheel package should be placed in this directory. In normal cases, you don’t need to use this variable, because py-build-cmake sets the CMake CMAKE_INSTALL_PREFIX variable and invokes CMake with the correct --prefix option during installation.	Environment
PY_BUILD_CMAKE_PYTHON_INTERPRETER	Path to the Python interpreter that was used to invoke py-build-cmake (sys.executable).	CMake
PY_BUILD_CMAKE_PYTHON_VERSION	The full version of the Python interpreter that was used to invoke py-build-cmake (platform.python_version()). Note that it includes any pre-release suffixes.	CMake
PY_BUILD_CMAKE_PYTHON_VERSION_MAJOR	Major version number of the Python interpreter that was used to invoke py-build-cmake (sys.version_info.major).	CMake
PY_BUILD_CMAKE_PYTHON_VERSION_MINOR	Minor version number of the Python interpreter that was used to invoke py-build-cmake (sys.version_info.minor).	CMake
PY_BUILD_CMAKE_PYTHON_VERSION_PATCH	Patch version number of the Python interpreter that was used to invoke py-build-cmake (sys.version_info.micro).	CMake
PY_BUILD_CMAKE_PYTHON_RELEASE_LEVEL	Release level of the Python interpreter that was used to invoke py-build-cmake (sys.version_info.releaselevel).	CMake
PY_BUILD_CMAKE_ABIFLAGS	The ABI flags of the Python interpreter that was used to invoke py-build-cmake (sys.abiflags).	CMake

Environment variables that affect the behavior of py-build-cmake

Variable	Description
PY_BUILD_CMAKE_VERBOSE	Enables verbose mode: prints more information about the py-build-cmake configuration, options passed to CMake, etc. Equivalent to passing the --verbose config option.
PY_BUILD_CMAKE_LOGLEVEL	Sets the level of the root logger. Can be used to silence all notifications or warnings. See https://docs.python.org/3/library/logging.html#levels for a list of valid levels. Equivalent to passing the --loglevel config option.
GITHUB_RUN_ATTEMPT	If this value is greater than one, automatically enables verbose mode. Explicitly set PY_BUILD_CMAKE_VERBOSE to false to disable this behavior.
NO_COLOR	Disables color output of the command line interface.
CLICOLOR_FORCE	Enable color output of the command line interface, even if not connected to a TTY.
_PYTHON_HOST_PLATFORM	Overrides the Python platform tag used for Wheel filenames. Note that this only changes the tag, it does not actually affect the build process.
DIST_EXTRA_CONFIG	On Windows, this variable can be set to the path of a configuration file that may contain the build_ext.plat_name and build_ext.library_dirs options. Support is limited to basic compatibility with cibuildwheel. See Cross-compilation § Windows for details.
ARCHFLAGS	On macOS, this variable can be set to enable automatic cross-compilation or to build universal2 Wheels. Possible values: -arch x86_64, -arch arm64 or -arch x86_64 -arch arm64. See Cross-compilation § macOS for details. Affects the platform tag of the generated Wheels, and passes the value on to CMake.
MACOSX_DEPLOYMENT_TARGET	Selects the macOS version to build for. Affects the platform tag of the generated Wheels, and passes the value on to CMake. Values should contain a major and minor version, separated by a dot. For example, 15.4.
SOURCE_DATE_EPOCH	Setting this to a Unix timestamp causes py-build-cmake to perform a reproducible build. The modification times of files in the generated sdist and Wheel archives are set to the given value.