It was attractive to consider using SYCL in GROMACS also for AMD GPUs, since there was already effort underway in GROMACS in that direction targeting Intel GPUs. The hipSYCL (https://github.com/illuhad/hipSYCL) open-source project run at Heidelberg University already supported CPUs, as well as Nvidia and AMD GPUs in SYCL  by extending existing clang toolchains, and was also funded by Intel to support the recent SYCL 2020 standard. We already wanted to use hipSYCL as our portability check of the  DPC++ code for Intel GPUs. We built a working relationship with the hipSYCL team led by Aksel Alpay.