Cyrusimap has support for all three of these baked in as well, and we really don't make as much of a big deal of it as we should. (and of course: JMAP Calendar

Cyrusimap has support for all three of these baked in as well, and we really don't make as much of a big deal of it as we should. (and of course: JMAP Calendars/Contacts/Files(eventually) will replace all that, we hope!)