Erlang on Xen uses a new highly compatible Erlang VM - codenamed LING - capable of running as a Xen guest OS. We have been running Erlang on the bare virtual iron since 2011.
LING VM runs directly on top of Xen hypervisor. It does not require Linux or anything. This takes away numerous administrative, scalability, and performance issues.
To give you a hands-on experience with Erlang on Xen, we created a public Amazon Machine Image (AMI).
The full runtime code compilation/loading capability added to Erlang on Xen. Now there is no need to call the build service to do .beam-to-.ling transformation.