rec {
   version="1.91";
   name="asymptote-1.91";
   hash="1bchzl8czhhjz47mr68m0ysj0dp09ks69qx3l46is3h6rj4bj1sp";
   url="http://downloads.sourceforge.net/asymptote/files/asymptote/${version}/asymptote-${version}.src.tgz";
   advertisedUrl="http://downloads.sourceforge.net/asymptote/files/asymptote/1.91/asymptote-1.91.src.tgz";
  
  
}