boot.loader.grub = {
    enable = true;
    copyKernels = true;                      # for ZFS
    zfsSupport = true;
    devices =
      [ "/dev/disk/by-id/ata-INTEL_SSDSA2MH080G1GN_CVEM850401CK080DGN"
        "/dev/disk/by-id/usb-WD_My_Passport_25E1_57584B3145323636414E4357-0:0"
      ];
    version = 2;
  };

  # Use the systemd-boot EFI boot loader.
  boot =
    { loader =
        { systemd-boot.enable = true;
          efi.canTouchEfiVariables = false;
        };
      supportedFilesystems = [ "zfs" ];
    };

  boot = {
    supportedFilesystems = [ "zfs" ];
  };