This talk will explain how to deploy OpenStack using the Xen hypervisor to run your virtual machines. It will start by describing the OpenStack architecture and its most important components. It will go into details on how to use DevStack to setup an OpenStack development environment based on Xen and Libvirt. It will cover the current status of Xen in OpenStack, in particular with regards to the OpenStack CI-loop, and the latest plans to improve Xen support in Nova. The audience will learn the most important OpenStack and Xen config options, the pitfalls to avoid in their deployment and how to tweak both of them to get the best performance and stability out of your OpenStack cloud.