This can be used to build nixos isos to run on an m1 Mac in Parallels/a VM.
Since the docker base image being used is aarch64 when run an an m1 Mac, it generates the matching iso which works out of the box (only tested in parallels).
./build.sh
This will write the iso to nixos.iso
Start parallels and select the created iso. You probably want to check CPU/RAM assignments when starting.
By following the official installation procedure
I went the UEFI route but MBR should also work.