All credit for the file-system itself to amadvance/snapraid.
Image is available at:
docker.io/ojford/snapraid
Data and parity disks are expected to be mounted at:
/mnt/{data,parity}/
An additional volume for snapraid.content (there must be P+1 for P parity mounts) is expected at:
/var/snapraid
GPL v3.0 as per amadvance/snapraid contained.