anchor.diff:            version = "0";
             license = null;
           }
  -        // packageInputs;
  +        // packageInputs
  +        // pkgs.lib.optionalAttrs doBenchmark {
  +          # `doBenchmark` needs to explicitly be set here because haskellPackages.mkDerivation defaults it to `false`.  If the user wants benchmark dependencies included in their development shell, it has to be explicitly enabled here.
  +          doBenchmark = true;
  +        };
   
           # This is a pseudo Haskell package derivation that contains all the
           # dependencies for the packages in `selected`.
  
positive.code:       , # Whether or not to generate a Hoogle database for all the
          # dependencies.
          withHoogle ? false
        , ...
        } @ args:
        let
  
negative.code:         # pkgWithCombinedDepsDevDrv :: Derivation
          pkgWithCombinedDepsDevDrv = pkgWithCombinedDeps.envFunc { inherit withHoogle; };
  
          mkDerivationArgs = builtins.removeAttrs args [ "packages" "withHoogle" "doBenchmark" ];
  
        in pkgWithCombinedDepsDevDrv.overrideAttrs (old: mkDerivationArgs // {
          nativeBuildInputs = old.nativeBuildInputs ++ mkDerivationArgs.nativeBuildInputs or [];
  