A software company founded in 2004 by Ian Pratt, Nick Gault and Moshe Bar, who developed the open-source Xen virtual machine monitor (the Xen hypervisor). XenSource managed the open-source project until 2008, when it was turned over to Xen.org. XenSource's enterprise version was acquired by Citrix and renamed XenServer. See
XenServer and
Xen.