Xapian is a highly adaptable toolkit which allows developers to easily add advanced indexing and search facilities to their own applications. It supports the Probabilistic Information Retrieval model and also supports a rich set of boolean query operators.
- Free Software/Open Source – licensed under the GPL.
- Supports Unicode (including codepoints beyond the BMP), and stores indexed data in UTF-8.
- Highly portable – runs on Linux, Mac OS X, FreeBSD, NetBSD, OpenBSD, Solaris, HP-UX, Tru64, IRIX, and probably other Unix platforms; as well as Microsoft Windows and OS/2.
- Written in C++. Perl bindings are available in the module Search::Xapian on CPAN. Java JNI bindings are included in the xapian-bindings module. We also support SWIG which can generate bindings for many languages. At present those for Python, PHP, Tcl, C#, and Ruby are working.
- Qoop – Online Auction Site
- Citebase – Searching academic papers
- Die Zeit – German Newspaper