anchor.diff:        '';
       };
   
  -    objstore = cfg : {
  +    objstore = cfg: {
   
         objstore.config-file = {
  -        toArgs = _opt : path : optionToArgs "objstore.config-file" path;
  +        toArgs = _opt: path: optionToArgs "objstore.config-file" path;
           option = mkOption {
             type = with types; nullOr str;
             default = if cfg.objstore.config == null then null
  
positive.code:     };
    };
  
    mkListParam = opt : description : {
      toArgs = _opt : listToArgs opt;
      option = mkOption {
        type = types.listOf types.str;
        default = [];
  
negative.code:     };
    };
  
    toYAML = name: attrs: pkgs.runCommandNoCC name {
      preferLocalBuild = true;
      json = builtins.toFile "${name}.json" (builtins.toJSON attrs);
      nativeBuildInputs = [ pkgs.remarshal ];
    } ''json2yaml -i $json -o $out'';
  
    thanos = cmd: "${cfg.package}/bin/thanos ${cmd}" +
      (let args = cfg."${cmd}".arguments;
       in optionalString (length args != 0) (" \\\n  " +
           concatStringsSep " \\\n  " args));
  
    argumentsOf = cmd: concatLists (collect isList
      (flip mapParamsRecursive params."${cmd}" (path: param:
        let opt = concatStringsSep "." path;
            v = getAttrFromPath path cfg."${cmd}";
        in param.toArgs opt v)));
  
    mkArgumentsOption = cmd: mkOption {
      type = types.listOf types.str;
      default = argumentsOf cmd;
      description = ''
  