I've done a lot of comparison between options in the email server space, and also in the high availability space. Because of the clamav and built in access to the spam daemon, Citadel server lacks only one thing to be the best replacement for hacked-together postfix+lmtp+caldav/webdav, etc., etc. The ability to have two of them, or ten of them, running 'hot' at the same time.
Now the only people who really need that are larger setups that can't tolerate the time it takes to bring a server down, duplicate/update the database, then bring it up on another server.
Mariadb has a replicated multi-master setup, so that each instance of the db could run on the same machine as the cit-server All the situation takes to be safely redundant is a third database instance, possibly offsite, to break data freshness ties in the case of ungraceful shutdowns.
I'm taking a look at making sql a backend option for citadel. This is not something that will happen by Tuesday.
That said, you can see why I'm really supporting the notion mentioned upstream of a key/setting table replacing the static config structure.
If you like we can talk about assigning that bit to me.
