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 CUDA suffixes.
• 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.

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.

Future improvements

• When https://github.com/rapidsai/dependency-file-generator/pull/48 is completed we can make dfg a dependency of this builder and use it to rewrite the dependency list instead of the manual logic here.

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.