I compiled the mac client for personal use but I have some problems of codesign-ing the package (it is not affecting using the app though.) My original post about this was on github.com. See here. Also I emailed @mario weeks ago in the hope that he could help us document this snippet in ./osx/build.sh in the code repo, like how to add our personal identities rather than use nextcloud developers’ identities.
sudo ~/client_theming/client/admin/osx/sign_app.sh ~/install/nextcloud.app 59FA8948AEBAE3F2222AE9BC020D6DA31DF821A7
sudo ./admin/osx/create_mac.sh ../install/ . 6A588D031B2B63991A49DB9C98B4C846D6D0EAC4