I finally released a new version of the Nextcloud charm just now after upgrading my own system.
A fresh deploy drops you in on version 18.0.3.0 at which point you can use the web gui for future upgrades.
The new version (Rev: 4) supports juju storage. This allows you to have the Nextcloud primary storage separated from the Nextcloud installation. There are also a few more examples in the documentation on how to test Nextcloud on a single server with postgresql charm.
It is known to work on MAAS and AWS at the moment, but chances are that it works on other clouds aswell, like lxd etc.
@timClicks wrote this excellent Tutorial using the Nextcloud charm to get a secure private cloud with online document editing and file-sharing.
I will be demoing this at Hack4Future 2020 Australia on the 1-3 May and for the Edgeryders community on the 8:th may.
For the next version, I’ll be addressing scaling of Nextcloud. If you like to help out, give me a shout.