{
  disko.devices = {
    disk = {
      # SD card — change device to /dev/sda if booting from USB instead
      main = {
        type = "disk";
        device = "/dev/mmcblk0";
        content = {
          type = "table";
          format = "mbr";
          partitions = [
            {
              # Raspberry Pi firmware partition — must be vfat and first
              name = "firmware";
              type = "primary";
              start = "1MiB";
              end = "512MiB";
              bootable = true;
              content = {
                type = "filesystem";
                format = "vfat";
                mountpoint = "/boot/firmware";
                mountOptions = [
                  "fmask=0077"
                  "dmask=0077"
                ];
              };
            }
            {
              # Root filesystem
              name = "root";
              type = "primary";
              start = "512MiB";
              end = "100%";
              content = {
                type = "filesystem";
                format = "ext4";
                mountpoint = "/";
              };
            }
          ];
        };
      };
    };
  };
}