Multi user access

I’ve read

But I’m still very surprised that DH has no way to allow multiple users access to the same dir/files. I understand the Unix ownership issue, but has any solution been created? Have ACL’s been implemented yet?

Ideally I don’t need a complex setup. I just need a master account to have access to all users files. But no other sharing among the regular users.

Just noticed the Unix Groups page.
It looks like this may be what I’m looking for…