anchor.diff:    packagesWithUpdateScriptAndMaintainer = maintainer':
       let
         maintainer =
  -        if ! builtins.hasAttr maintainer' pkgs.lib.maintainers then
  +        if ! builtins.hasAttr maintainer' lib.maintainers then
             builtins.throw "Maintainer with name `${maintainer'} does not exist in `maintainers/maintainer-list.nix`."
           else
  -          builtins.getAttr maintainer' pkgs.lib.maintainers;
  +          builtins.getAttr maintainer' lib.maintainers;
       in
         packagesWith (name: pkg: builtins.hasAttr "updateScript" pkg &&
                                    (if builtins.hasAttr "maintainers" pkg.meta
  
positive.code: # TODO: add assert statements
  
  let
    /* Remove duplicate elements from the list based on some extracted value. O(n^2) complexity.
     */
    nubOn = f: list:
  
negative.code: 
    packageData = package: {
      name = package.name;
      pname = lib.getName package;
      updateScript = map builtins.toString (lib.toList package.updateScript);
    };
  
    packagesJson = pkgs.writeText "packages.json" (builtins.toJSON (map packageData packages));
  
    optionalArgs =
      lib.optional (max-workers != null) "--max-workers=${max-workers}"
      ++ lib.optional (keep-going == "true") "--keep-going";
  
    args = [ packagesJson ] ++ optionalArgs;
  
  