anchor.diff:            Whether fish should use completion files provided by other packages.
           '';
         };
  -      
  +
         vendor.functions.enable = mkOption {
           type = types.bool;
           default = true;
  
positive.code: 
    config = mkIf cfg.enable {
  
      environment.etc."fish/foreign-env/shellInit".text = cfge.shellInit;
      environment.etc."fish/foreign-env/loginShellInit".text = cfge.loginShellInit;
      environment.etc."fish/foreign-env/interactiveShellInit".text = cfge.interactiveShellInit;
  
      environment.etc."fish/nixos-env-preinit.fish".text = ''
        # This happens before $__fish_datadir/config.fish sets fish_function_path, so it is currently
        # unset. We set it and then completely erase it, leaving its configuration to $__fish_datadir/config.fish
        set fish_function_path ${pkgs.fish-foreign-env}/share/fish-foreign-env/functions $__fish_datadir/functions
        
        # source the NixOS environment config
        if [ -z "$__NIX_DARWIN_SET_ENVIRONMENT_DONE" ]
            fenv source ${config.system.build.setEnvironment}
        end
  
        # clear fish_function_path so that it will be correctly set when we return to $__fish_datadir/config.fish
        set -e fish_function_path
      '';
  
      environment.etc."fish/config.fish".text = ''
        # /etc/fish/config.fish: DO NOT EDIT -- this file has been generated automatically.
  
        # if we haven't sourced the general config, do it
        if not set -q __fish_nix_darwin_general_config_sourced
          set fish_function_path ${pkgs.fish-foreign-env}/share/fish-foreign-env/functions $fish_function_path
          fenv source /etc/fish/foreign-env/shellInit > /dev/null
          set -e fish_function_path[1]
          
          ${cfg.shellInit}
  
          # and leave a note so we don't source this config section again from
          # this very shell (children will source the general config anew)
          set -g __fish_nix_darwin_general_config_sourced 1
        end
  
        # if we haven't sourced the login config, do it
        status --is-login; and not set -q __fish_nix_darwin_login_config_sourced
        and begin
          set fish_function_path ${pkgs.fish-foreign-env}/share/fish-foreign-env/functions $fish_function_path
          fenv source /etc/fish/foreign-env/loginShellInit > /dev/null
          set -e fish_function_path[1]
          
          ${cfg.loginShellInit}
  
          # and leave a note so we don't source this config section again from
          # this very shell (children will source the general config anew)
          set -g __fish_nix_darwin_login_config_sourced 1
        end
  
        # if we haven't sourced the interactive config, do it
        status --is-interactive; and not set -q __fish_nix_darwin_interactive_config_sourced
        and begin
          ${fishAliases}
          
  
          set fish_function_path ${pkgs.fish-foreign-env}/share/fish-foreign-env/functions $fish_function_path
          fenv source /etc/fish/foreign-env/interactiveShellInit > /dev/null
          set -e fish_function_path[1]
          
          ${cfg.promptInit}
          ${cfg.interactiveShellInit}
  
          # and leave a note so we don't source this config section again from
          # this very shell (children will source the general config anew,
          # allowing configuration changes in, e.g, aliases, to propagate)
          set -g __fish_nix_darwin_interactive_config_sourced 1
        end
      '';
  
      # include programs that bring their own completions
      environment.pathsToLink = []
        ++ optional cfg.vendor.config.enable "/share/fish/vendor_conf.d"
        ++ optional cfg.vendor.completions.enable "/share/fish/vendor_completions.d"
        ++ optional cfg.vendor.functions.enable "/share/fish/vendor_functions.d";
      
      environment.systemPackages = [ pkgs.fish ];
  
    };
  
  }
  
negative.code:     mapAttrsFlatten (k: v: "alias ${k} '${v}'") cfg.shellAliases
    );
  
    envShellInit = pkgs.writeText "shellInit" cfge.shellInit;
  
    envLoginShellInit = pkgs.writeText "loginShellInit" cfge.loginShellInit;
  
    envInteractiveShellInit = pkgs.writeText "interactiveShellInit" cfge.interactiveShellInit;
  
    fenv = pkgs.fish-foreign-env or pkgs.fishPlugins.foreign-env;
  
    sourceEnv = file:
    if cfg.useBabelfish then
      "source /etc/fish/${file}.fish"
    else
      ''
        set fish_function_path ${fenv}/share/fish-foreign-env/functions $fish_function_path
        fenv source /etc/fish/foreign-env/${file} > /dev/null
        set -e fish_function_path[1]
      '';
  
    babelfishTranslate = path: name:
      pkgs.runCommand "${name}.fish" {
        nativeBuildInputs = [ cfg.babelfishPackage ];
      } "${cfg.babelfishPackage}/bin/babelfish < ${path} > $out;";
  
  in
  
  {
  