Talks:
Increase eZ power with EzCoreExtraBundle - eZ Conference 2016
Going crazy with HTTP caching - SymfonyLive Paris 2015
Étendre Symfony, les bonnes pratiques - SymfonyLive Paris 2014
(French)
Demystify migration to eZ 5.x - eZ Days Oslo 2014
eZ Publish 5 and Backwards Compatibility - eZ Summer Camp 2013
eZ Publish 5 Cache unleashed - eZ Summer Camp 2013
Links:
Offical location for eZ related slides
For older content you might want to check
my blog
(mostly french).