Lucandra is a project that combines Lucene/Solr indexing and search capabilities with Cassandra for storage. It addresses issues with scaling Lucene/Solr by leveraging Cassandra's ability to horizontally scale writes and queries. Lucandra stores Lucene indexes and term vectors in Cassandra to allow distributed indexing and searching across nodes. It has been used successfully in production systems like sparse.ly for twitter search and Wikassandra for Wikipedia search.