{ ... }:
{
    fileSystems."/mnt/hdd" = {
        device = "/dev/mapper/hdd";
        fsType = "btrfs";
        options = [ "compression=zstd:3" "autodefrag" "nofail" ];

        encrypted = {
            enable = true;
            label = "hdd";
            blkDev = "/dev/disk/by-uuid/eab5e1d6-6956-46fd-b3ac-5fcf525e1df8";
            keyFile = "/mnt-root/root/hdd.key";
        };
    };
}