While reading Andrew’s message on syscall origin checking, I realized that UX/RT could potentially replace Linux VMs in Core Platform applications. I imagine that this would require changes to both the Core Platform and UX/RT. Andrew, would you be interested in adding a hosting interface to UX/RT, so that static systems such as the Core Platform can use UX/RT as a Linux VM replacement? UX/RT seems like a fantastic alternative, with both better security and (eventually) better performance. I would imagine that it also would use less memory than a Linux VM. Gernot (and the rest of the seL4 team): would it be possible to support running other seL4-based systems as protection domains in a future version of the Core Platform? Such systems would be opaque from the Core Platform’s perspective, but they might need capabilities that normal protection domains are not provided. Of course, they would not be granted any capabilities that would allow them to violate system security. Yes, I know that one can run seL4 in a VM, but it seems rather wasteful to do so. Sincerely, Demi