Oh, hey, NixOS has an installer ISO! I hadn't seen that before.
I just went to fire up a new NixOS VM and instinctively reached for cloning an old VM, rather than do all the bazillion manual install steps, but this is much easier!
@bradfitz You can also use Nix to generate a VM image. If you have (or want to have) Nix available somewhere outside of that VM that is likely simpler than going through installation.
@robryk @bradfitz Can confirm that this works and is awesome.