nixops-util-scripts.nix

{
  environment.etc = {

    # Utility scripts. Must be manually symlinked into /root
    "my-scripts".source = let
      scripts = [
          {
            "script-name.sh" = ''
              echo 'script content';
            '';
          }
          (
            let condition = false; in
            if condition
            then { "other-script.sh" = "echo 'other content'"; }
            else null  # gets excluded
          )
        ];
      in pkgs.stdenv.mkDerivation {
        name = "etc-util-scripts";
        dontUnpack = true;
        installPhase = ''
        mkdir -p $out
        ${ let inherit (pkgs.lib) trivial attrsets strings lists; in
            trivial.pipe scripts [
              (lists.filter (x: x != null))
              (lists.foldl trivial.mergeAttrs {})
              (attrsets.mapAttrsToList
                (name: text: "cp ${pkgs.writeScript name text} $out/${name}\n"))
              strings.concatStrings
            ] }
        '';
      };

  };
}