anchor.diff:  
   let
     name    = "maxima";
  -  version = "5.25.1";
  +  version = "5.26.0";
   
     searchPath =
       stdenv.lib.makeSearchPath "bin"
  
positive.code: 
    src = fetchurl {
      url = "mirror://sourceforge/${name}/${name}-${version}.tar.gz";
      sha256 = "8e98ad742151e52edb56337bd62c8a9749f7b598cb6ed4e991980e0e6f89706a";
    };
  
    buildInputs = [sbcl texinfo perl makeWrapper];
  
negative.code:     ln -s ../maxima/${version}/doc $out/share/doc/maxima
    '';
  
    # Failures in the regression test suite are not going to abort the
    # build process. We run the suite mostly so that potential errors show
    # up in the build log. See also:
    # <http://sourceforge.net/tracker/?func=detail&aid=3365831&group_id=4933&atid=104933>.
    doCheck = true;
  
  