(:name nix-mode
       :type http
       :url "https://raw.github.com/NixOS/nix/master/misc/emacs/nix-mode.el"
       :description "Major mode for editing Nix expressions"
       :prepare (progn
                  (autoload 'nix-mode "nix-mode" nil t)
                  (add-to-list 'auto-mode-alist '("\\.nix$" . nix-mode))))