Re: Citrix?
Sorry but, I think you may be confusing XenServer and Xen.
Xen the hypervisor is a Linux foundation project, it is indeed used by Amazon but the API Amazon developed is not open source.
XenServer is a Citrix product and an open source project (impossible to build by anyone else than Citrix team but still open source) - It includes Xen hypervisor and the Xen API (basically, it's a turnkey Xen)
XCP-ng forked it because the XenServer project is only open source by name and only contributor to the project is Citrix. Honestly, the lack of documentation and transparency on that project make it impossible for anyone else to build a proper XenServer from the sources.
Biting the hand that feeds IT
