OS over Metal

The Den is the exception that proves the rule: it runs nothing between the operating system and the work. Its two machines run Ubuntu directly — one hosting life-critical services natively, the other running personal applications in Docker containers. There’s no hypervisor of its own carving the box into rooms, because the Den is already small and single-purpose, and every layer you add is a layer that can fail.

“Bare metal” is the standard term for this — the OS running directly on the host, with no virtualization of the enclave’s own beneath it. It’s the right call where simplicity and predictability matter more than the flexibility of splitting one box into many.