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Open Source	DataparkSearch Engine	is a full-featured open source web-based search engine released under the GNU General Public License and designed to organize search within a website, group of websites, intranet or local system.
	Egothor→LIS Cafe-Home	is an Open Source, high-performance, full-featured text search engine written entirely in Java. It can be configured as a standalone engine, metasearcher, peer-to-peer HUB, etc.
	gonzui→LIS Cafe-Home	is a source code search engine for accelerating open source software development - a source code search engine that covers vast quantities of open source codes available on the Internet.
	Grub→LIS Cafe-Home	started back in 2000 with a simple concept of distributing part of the search process pipeline: crawling. Their website claims, "We want to help fix search."
	ht://Dig→LIS Cafe-Home	is a complete world wide web indexing and searching system for a domain or intranet. ht://Dig is meant to cover the search needs for a single company, campus, or web site.
	iSearch	The iSearch PHP search engine allows you to build a searchable database for your web site. Visitors can search for key words and a list of any pages that match is returned to them.
	Lucene→LIS Cafe-Home	Apache Lucene is a high-performance, full-featured text search engine library written entirely in Java. Full-text search & cross-platform. Apache Lucene is an open source project available for free download.
	Lemur Toolkit→LIS Cafe-Home	The Lemur Toolkit is a open-source toolkit designed to facilitate research in language modeling and information retrieval. Lemur supports a wide range of industrial and research language applications.
	mnoGoSearch:	Web search engine software.
	Namazu→LIS Cafe-Home	is a full-text search engine intended for easy use. Not only does it work as a small or medium scale Web search engine, but also as a personal search. (Namazu means "Catfish" in Japanese.)
		Nutch is an effort to build an open source search engine based on Lucene Java for the search and index component. The fetcher ("robot" or "web crawler") has been written from scratch solely for this project.
	OpenFTS:→LIS Cafe-Home	OpenSource Full Text Search is an advanced PostgreSQL-based search engine that provides online indexing of data and relevance ranking for database searching.
	Sciencenet:→LIS Cafe-Home	For scientific knowledge based on YaCy Technology. Current search engines are based on popularity and/or sponsored links. This makes it difficult for scientists/students/teachers. Sciencenet is the solution.
	Sphinx→LIS Cafe-Home	is a free software search engine designed with indexing database content in mind. It currently supports MySQL and PostgreSQLnatively. It is distributed under the terms of the GNU General Public License v2.
	SWISH-Enhanced→LIS Cafe-Home	(Simple Web Indexing System for Humans - Enhanced) is a fast, powerful, flexible, free, and easy to use system for indexing collections of Web pages or other text files.
	Terrier→LIS Cafe-Home	is software for the rapid development of Web, intranet and desktop search engines.A modular platform for the rapid development of large-scale Information Retrieval applications.
	Wikia Search:	Jimmy Wales and Wikia aim to create a an open source Internet search engine, to which the community can contribute.
	Xapian→LIS Cafe-Home	is an Open Source Search Engine Library, released under the GPL. It's written in C++, with bindings to allow use from Perl, Python, PHP, Java, Tcl, C# and Ruby (so far!)
	YaCy→LIS Cafe-Home	is a scalable personal web crawler and web search engine. One YaCy installation can store more than 10 million documents, but in a community of search peers YaCy can provide a search index of unlimited size.
	Zettair→LIS Cafe-Home	is a compact and fast text search engine designed and written by the Search Engine Group at RMIT University.  It was formerly known as Lucy.