Creating SMB shares writable from iOS devices using a magical incantation

The Files app on iOS can read from and write to SMB shares (much to my surprise), but hosting an iOS-writable SMB share from Samba requires a magical incantation in smb.conf (as mentioned here):

vfs objects = catia fruit streams_xattr

I have not investigated what all this means or why it's needed or any security implications, so make sure to do your own research.