[devinus]

Simple answer: you don't. Longer answer: It depends. Do you want to use yum or apt-get to install programs? If you like CentOS, create a CentOS container with Docker and begin installing programs using yum! Ubuntu? Spool up an Ubuntu container and apt-get away! CoreOS is just the cradle upon which you can run the userland of any distribution you please.

[amalag]

So CoreOS is the simple host OS, thank you for the clarification, i thought it was a minimal guest OS.