It's a unikernel of sorts called Erlang on Zen (the VM implementation they wrote is called Ling). It does not use the BEAM runtime so you'll likely need to recompile the Erlang code but otherwise, Erlang is a simple language so I expect most things would work.

Given that this was written roughly 4 years ago (guessing by some dates on the site), its not clear what their support looks like for newer features like maps might be.

Performance looks good (relative to BEAM) but they are also single-threaded which means you'd need to cluster your instances to do multi-processing... and I'm not sure that'd mix well with ephemeral nodes. They talk a little more about this on their site: http://erlangonxen.org/more/clustering