zfs-allow is a terminal UI and scripting front-end for ZFS delegated
administration (zfs allow / zfs unallow). It shows the delegations of a
dataset the way zfs allow prints them, lets you edit them as a checklist in
which every permission is described, and turns the edits into the exact
zfs allow / zfs unallow commands, shown for review before they run.
Pre-flight checks point out what the commands will not achieve: create
without mount, vfs.usermount=0, a mount point the grantee cannot create
directories in, what an unprivileged delegator cannot do. It also shows the
effective permissions of a user on a dataset with their sources, and offers
all of that non-interactively for scripts (-add, -remove, -effective,
-where, -dump/-restore, dry run, -check).