Similiar to the “old” owncloud-files package, which allows to have an up to date version of it while still beiing able to maintain your custom setup around it (webserver stack, database server, …), i’ve created a package for Nextcloud.
It get’s uploaded to my repo, so can throw this in a mix with MariaDB and Dotdeb PHP7.0 repos to easily create your Nextcloud instance.