Search engine library This package contains the core Xapian runtime library. The Xapian search engine library is a highly adaptable toolkit which allows developers to easily add advanced indexing and search facilities to their own applications. It implements the probabilistic model of information retrieval, and provides facilities for performing ranked free-text searches, relevance feedback, phrase searching, boolean searching, stemming, and simultaneous update and searching. It is highly scalable, and is capable of working with collections containing hundreds of millions of documents.