Sharing folders on a Ubuntu-based UCS client

Recently I’ve setup a Ubuntu Linux client for a UCS server, according to the manual https://docs.software-univention.de/domain-4.2.html#ext-dom-ubuntu .
It’s working well: the domain users can logon to the client, and they can easily connect to shared folders on the UCS server or on other Windows-based computers in the domain.
However, what about the opposite direction? I would also like to share some folders on the Linux client. Unfortunately I didn’t find any documentation on setting up Samba to do that.
It might be possible to treat the UCS server (which is running AD services) as a Windows server and have Samba join the AD domain, but I don’t think that would play together well with the Linux integration used before…?

The only way that could provide the feature that you are looking for would be to join the Ubuntu-Client into the Samba 4 part of UCS in the same way is it would join into a Windows Active Directory. This indeed another type of integration than described in the standard documentation.