u-boot & ZFS

[ChrisO]

Hi

I searched for u-boot ZFS references and all I found was several years old, but I suppose u-boot can cope with ZFS.
So, my question is: is it possible to boot Linux from ZFS or at least boot from let's say SD-card with ext4 FS and mount a ZFS volume as root filesystem?
I had a look at Armbian, installed all needed, user-space and kernel modules. After booting from SD card I can use ZFS on attached SATA SSD w/o any problem.
I also see ZFS libs and kernel modules in initrd,  so it looks like the necessary things are there.
Don't know where to start.
I would be very thankful for any help.

Regards.
Chris