The cccl folder is a git submodule for the CCCL project, the new home for Thrust, CUB, and libcu++. The CCCL headers are used at both build- and run- time. For further information on CUB, see the CCCL repo.

The jitify folder is a git submodule for the Jitify project. Including the Jitify header as a submodule for building the cupy.cuda.jitify module. For further information on Jitify, see the Jitify repo.

The dlpack folder is a git submodule for the DLPack project. Including the Jitify header as a submodule for building the cupy._core.dlpack module. For further information on DLPack, see the DLPack repo.