anchor.diff:      sha256 = "0gipgb939vy9m66d3k8il98rvvwczyaw2ixr8yn6icds9c3nrsz4";
     };
   
  -  buildInputs = [];
  +  buildInputs = optional stdenv.isDarwin darwin.cctools;
   
     configureFlags = optional disablePosixThreads
       [ "--disable-posix-threads" ];
  
positive.code:     description = "Replacement for the old crypt() package and crypt(1) command, with extensions";
      homepage = http://mcrypt.sourceforge.net;
      license = "GPL";
    };
  }
  
negative.code: { stdenv, fetchurl, darwin, disablePosixThreads ? false }:
  
  with stdenv.lib;
  
  