[Koha] Koha training and certification

Hello all, I am looking for information regarding Koha training and certification, if there's any. Any information regarding institutions or organizations providing these services is welcome. The training and certification I'm looking for is both at a technical level (Perl programming, Koha command line utilities, Zebra indexing and configuration, database schema, etc) as well as at a user level (How to perform an advanced search, how to catalog, using the circulation module, using the acquisitions module, system preferences and so on and so forth). As always thanks a bunch, Pedro Amorim