nixbsd-config/system/pearbutter/boot-config.nix

{ ... }:
{
  nixpkgs.hostPlatform = "x86_64-freebsd";
  nixpkgs.config.freebsdBranch = "releng/14.0";

  networking.hostName = "pearbutter";

  fileSystems."/" = {
    device = "/dev/gpt/pearbutter-root";
    fsType = "ufs";
  };

  fileSystems."/boot" = {
    device = "/dev/gpt/pearbutter-efi";
    fsType = "msdosfs";
  };
}