From http://lists.alioth.debian.org/pipermail/pkg-mysql-maint/2017-April/010816.html :

My main goal is to immediately pick up on any pushes to master that
result in a FTBFS.

I put this together with it's PPA daily build facility for
rudimentary automatic daily builds against mysql-5.7/debian/master from
mysql.git on Alioth and from master branch of mariadb-10.1

Available at

Upstream MariaDB also has public CI system, see e.g. http://buildbot.askmonty.org/buildbot/grid?branch=10.2&category=main