{ nixosSystem, home-manager, nixpkgs-unstable, ... }: {
  sterni = nixosSystem {
    system = "x86_64-linux";
    modules = [
      ./configs/sterni/configuration.nix
      home-manager.nixosModules.home-manager
      {
        home-manager.useGlobalPkgs = true;
        home-manager.useUserPackages = true;
      }
      ({ pkgs, ... }: {
        # defined overlays injected by the nixflake
        nixpkgs.overlays = [
          (_self: _super: {
            # we assign the overlay created before to the overlays of nixpkgs.
            unstable = nixpkgs-unstable.legacyPackages.${pkgs.system};
          })
        ];

        # imports of modules
        imports = [ <backup-module> <krops-lib> <cluster-module> <modules> ];
      })
    ];
  };
}