RAPIDS PEP517 build backend

rapids-build-backend is an adapter around PEP517 builders that provides support for key RAPIDS requirements. It currently support scikit-build-core and setuptools as the wrapped builder. The package's primary purpose is to automate the various bits of preprocessing that are typically done to RAPIDS package metadata prior to publishing packages. This includes the following notable changes:

• Running rapids-dependency-file-generator to get the dependencies for the CUDA version and architecture.
• Modifying the package name to include a CUDA suffix (e.g. "rmm" -> "rmm-cu11")
• Updating the git commit embedded in the importable package.

Since some of these modifications are only desirable in certain scenarios (wheel vs conda builds vs editable installs), all of these functions are customizable via the project's configuration in pyproject.toml. In cases where more dynamic customization is sensible, suitable environment variables and config_settings are supported during builds of distributions.

Supported configuration

Any option without a default is required.

Option	Definition	Type	Default	Supports dynamic modification
build-backend	The wrapped build backend (e.g. setuptools.build_meta)	string		N
commit-files	List of files in which to write the git commit hash	list[str]	["<project_name>/GIT_COMMIT"]	N
dependencies-file	The path to the dependencies.yaml file to use	string	"dependencies.yaml"	Y
disable-cuda	If true, CUDA version in build environment is ignored when setting package name and dependencies	bool	false	Y
matrix-entry	A ;-separated list of =-delimited key/value pairs	string	""	Y
requires	List of build requirements (in addition to build-system.requires)	list[str]	[]	N

Outstanding questions

• How should we split up build requirements between build-system and tool.rapids-build-backend? In theory any dependency that doesn't need suffixing could also go into build-system.requires. I think it's easier to teach that all dependencies other than rapids-build-backend itself should to into tool.rapids-build-backend, but I don't know how others feel.

Rejected ideas

• We could also include the rewrite of VERSION that we use for RAPIDS builds, but this is really more specific to our release process than the general process of building our wheels. I don't think someone building a wheel locally should see the same version as what we produce via CI. If we really wanted we could pull dunamai as a dependency and write a different version here, though.