Elasticsearch
Elasticsearch is a free and open source search server based on the Lucene software library. It provides a distributed, multitenant-capable full-text search engine with a RESTful web interface and schema-free JSON documents "so you can discover the expected and uncover the unexpected". It integrates natively with Tiki Wiki CMS Groupware, and a related project named Kibana permits visualizations. The source code of Elasticsearch is available under the Apache version 2.0 software license.
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