According to wikipedia, DevConf.CZ is...
an annual, free, Red Hat sponsored community conference for developers, admins, DevOps engineers, testers, documentation writers and other contributors to open source technologies. The conference includes topics on Linux, Middleware, Virtualization, Storage and Cloud. At DevConf.cz, FLOSS communities sync, share, and hack on upstream projects together in the beautiful city of Brno, Czech Republic.
There were a lot of fantastic presentations at the 2020 conference held back in January... and 212 of have been posted to YouTube.
As a sample, here's Dan Walsh updating us on the State of Container Security. Enjoy!