{
  description = "Thor system configuration";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/release-21.11";

    home-manager = {
      url = "github:nix-community/home-manager/release-21.11";
      inputs.nixpkgs.follows = "nixpkgs";
    };

    unstable.url = "github:NixOS/nixpkgs/nixos-unstable";

    home-manager-unstable = {
      url = "github:nix-community/home-manager";
      inputs.nixpkgs.follows = "unstable";
    };

    flake-utils.url = "github:numtide/flake-utils";

    nixos-hardware.url = "github:NixOS/nixos-hardware";

    rust-overlay = {
      url = "github:oxalica/rust-overlay";
      inputs.nixpkgs.follows = "nixpkgs";
      inputs.flake-utils.follows = "flake-utils";
    };

    tex2nix = {
      url = github:Mic92/tex2nix;
      inputs.nixpkgs.follows = "nixpkgs";
      inputs.flake-utils.follows = "flake-utils";
    };
  };

  outputs =
    { self
    , nixpkgs
    , home-manager
    , unstable
    , home-manager-unstable
    , flake-utils
    , nixos-hardware
    , rust-overlay
    , tex2nix
    }:
    let
      system = "x86_64-linux";
      overlays = [
        (import ./rice.nix)
        (rust-overlay.overlay)
        (final: prev: { inherit (tex2nix.packages.${system}) tex2nix; })
        (final: prev: {
          # cocktail-bar-cli = final.callPackage ./custom/cocktail-bar-cli { };
          update-background = final.callPackage ./custom/update-background { backgrounds_directory = "$HOME/Immagini/Sfondi/1080+/1440+"; };
          lockscreen = final.callPackage ./custom/lockscreen {
            palette = final.rice.colorPalette;
            font = final.rice.font.normal;
          };
        })
        (final: prev: { unstable = unstablePkgs; })
      ];
      nixpkgsSettings = {
        inherit overlays system;
        config = {
          allowUnfree = true;
          permittedInsecurePackages = [ "electron-9.4.4" ]; # authy dependency
        };
      };
      pkgs = import nixpkgs nixpkgsSettings;
      unstablePkgs = import nixpkgs nixpkgsSettings;

      homeManagerSettings = {
        home-manager = {
          useGlobalPkgs = true;
          useUserPackages = true;
        };
      };

      odinBaseModules = [
        { nixpkgs = nixpkgsSettings; }
        ./odin/hardware-configuration.nix
        nixos-hardware.nixosModules.common-cpu-intel
        nixos-hardware.nixosModules.common-pc-laptop
        nixos-hardware.nixosModules.common-pc-laptop-ssd
        ./odin/base.nix
      ];

      thorBaseModules = [
        { nixpkgs = nixpkgsSettings; }
        ./thor/hardware-configuration.nix
        nixos-hardware.nixosModules.common-cpu-amd
        nixos-hardware.nixosModules.common-pc-ssd
        ./thor/configuration.nix
      ];

      odinStable = extraModules: nixpkgs.lib.nixosSystem {
        inherit system;
        modules = odinBaseModules ++ [
          home-manager.nixosModules.home-manager
          homeManagerSettings
          { home-manager.users.bertof = import ./odin.nix; }
        ] ++ extraModules;
      };

      odinUnstable = extraModules: unstable.lib.nixosSystem {
        inherit system;
        modules = odinBaseModules ++ [
          home-manager-unstable.nixosModules.home-manager
          homeManagerSettings
          { home-manager.users.bertof = import ./odin.nix; }
        ] ++ extraModules;
      };

      thorStable = extraModules: nixpkgs.lib.nixosSystem {
        inherit system;
        modules = thorBaseModules ++ [
          home-manager.nixosModules.home-manager
          homeManagerSettings
          { home-manager.users.bertof = import ./thor.nix; }
        ] ++ extraModules;
      };

      thorUnstable = extraModules: unstable.lib.nixosSystem {
        inherit system;
        modules = thorBaseModules ++ [
          home-manager-unstable.nixosModules.home-manager
          homeManagerSettings
          { home-manager.users.bertof = import ./thor.nix; }
        ] ++ extraModules;
      };

    in
    {
      packages.${system} = pkgs;

      nixosConfigurations = rec {

        thor = thor-unstable;

        thor-stable = thorStable [ ./nixos_modules/pro_audio.nix ];
        thor-unstable = thorUnstable [ ./nixos_modules/pro_audio.nix ];
        thor-big-data = thorUnstable [ ./nixos_modules/pro_audio.nix ./nixos_modules/big_data.nix ];

        odin = odin-intel-unstable;

        odin-intel-unstable = odinUnstable [ ./odin/odin-intel.nix ./nixos_modules/pro_audio.nix ];
        odin-nvidia-unstable = odinUnstable [ ./odin/odin-nvidia.nix ./nixos_modules/pro_audio.nix ];
        odin-intel-stable = odinStable [ ./odin/odin-intel.nix ./nixos_modules/pro_audio.nix ];
        odin-nvidia-stable = odinStable [ ./odin/odin-nvidia.nix ./nixos_modules/pro_audio.nix ];

      };
    };
}