What do you mean by a ZFS compatibility layer? There is a Windows port: https://github.com/openzfsonwindows/openzfs https://github.com/openzfsonwindows/openzfs

What do you mean by a ZFS compatibility layer? There is a Windows port: https://github.com/openzfsonwindows/openzfs https://github.com/openzfsonwindows/openzfs Note that it is a beta.