anchor.diff:  
   let
     name    = "maxima";
  -  version = "5.41.0";
  +  version = "5.42.2";
   
     searchPath =
       stdenv.lib.makeBinPath
  
positive.code:     ./known-ecl-failures.patch
    ];
  
    # Failures in the regression test suite won't abort the build process. We run
    # the suite only so that potential errors show up in the build log. See also:
    # https://sourceforge.net/tracker/?func=detail&aid=3365831&group_id=4933&atid=104933.
    doCheck = true;
  
    enableParallelBuilding = true;
  
  
negative.code: 
    src = fetchurl {
      url = "mirror://sourceforge/${name}/${name}-${version}.tar.gz";
      sha256 = "0kdncy6137sg3rradirxzj10mkcvafxd892zlclwhr9sa7b12zhn";
    };
  
    buildInputs = stdenv.lib.filter (x: x != null) [
      sbcl ecl texinfo perl python makeWrapper
      gnuplot   # required in the test suite
    ];
  
    postInstall = ''
  