Where to Get FFTX
FFTX is available on GitHub as open source under a non-viral BSD-style license: https://github.com/spiral-software/fftx/
It builds and runs on CPU and GPU backends on several platforms:
CPU backend on Windows, Linux, macOS, Raspberry Pi;
CUDA backend on the Perlmutter system at the National Energy Research Scientific Computing Center;
HIP backend on the Frontier system at the Oak Ridge Leadership Computing Facility;
SYCL backend on the Aurora system at the Argonne Leadership Computing Facility.
See the README on GitHub for more information.