anchor.diff:        x86_64-linux = "1949argajiyqyq09824yj3wjyv88gd8wbf20xh895saqfykiq880";
         i686-linux = "0w0f4fwr2ijhx59i7ppicbh05hfmq7vffmgl7lal6im945m29vch";
         x86_64-darwin = "01n0rf8zh551vv8wq3h0ifnsai0fz9a77yq87xx81y9dscl9h099";
  +      aarch64-linux = "0sns7l4q3z82qi3dc2r4p63f4s8hvifqzgq56ykwyrvawynjhd53";
       };
     };
   
  
positive.code:     i686-linux = "linux-i686";
      x86_64-darwin = "darwin-x86_64";
      aarch64-darwin = "darwin-universal";
    };
  
    arch = archs.${stdenv.system} or (throw "system ${stdenv.system} not supported");
    isAarch64Darwin = stdenv.system == "aarch64-darwin";
  
    checkInputs = [ git gmp openssl readline libxml2 libyaml ];
  
    genericBinary = { version, sha256s, rel ? 1 }:
      stdenv.mkDerivation rec {
  
negative.code:       inherit version;
  
        src = fetchurl {
          url = binaryUrl version rel;
          sha256 = sha256s.${stdenv.system};
        };
  
  