configuration.nix

{ config, pkgs, ... }:
let subvol-mount = path: { name = path;
                           value = { fsType = "btrfs";
                                     label = "root";
                                     options = [ "defaults" 
                                                 "subvol=${path}"
                                               ];
                                   };
                         };
    subvols = builtins.listToAttrs (map subvol-mount
      [ "/etc-persistent"
        "/home-persistent/shlevy"
        "/nix"
        "/var/lib/cups"
        "/var/log"
        "/var/lib/kanboard"
      ]);
in {
  fileSystems =
    ({ "/" = { device = "tmpfs";
               fsType = "tmpfs";
               options = [ "defaults" "mode=755" ];
             };
       "/boot" = { label = "ESP";
                   fsType = "vfat";
                 };
     } // subvols);
  environment.etc =
    { systemd-mutable.source = "/etc-persistent/systemd-mutable";
      "nixos/configuration.nix".text =
          "import /etc-persistent/nixos/configuration.nix\n";
       machine-id.text = "2c83968a55a1443c971598294d34f9ed\n";
    }; 
}