cql-ruby is a ruby gem for parsing CQL, and serializing parse trees back to CQL, to xCQL, or to a solr query. A new version has been released, 0.8.0, available from gem update/install. The new version improves greatly on the #to_solr serialization as a solr query, providing support for translation from more CQL relations than previously, fixing a couple bugs, and making #to_solr raise appropriate exceptions if you try to convert CQL that is not supported for #to_solr. See: http://cql-ruby.rubyforge.org/svn/trunk/lib/cql_ruby/cql_to_solr.rb That's the only change from the previous version, improved #to_solr. I wrote the improved #to_solr, Chick Markley wrote the original cql-ruby gem, which was a port of the Java CQL parsing code by Mike Taylor. Ain't open source grand? Jonathan