Lucene and Solr are open-source search engines developed by the Apache Software Foundation (ASF). Lucene was created in 1999 and donated to ASF in 2001. Solr was created in 2004 and donated to ASF in 2006. Both projects have large user communities and are maintained through a collaborative process within ASF. ASF provides organizational support for many open-source projects through a meritocratic process.