Somewhat related is MirageOS, a microkernel library for producing applications that run directly in a hypervisor, like Xen. So no virtual environment necessary.

Somewhat related is MirageOS, a microkernel library for producing applications that run directly in a hypervisor, like Xen. So no virtual environment necessary. And thanks to the memory safety of OCaml (given certain assumptions about the style of programming, because any sufficiently versatile language comes with footguns) you don’t even really need the virtual memory system and other conveniences of a modern operating system.