The initial version of Carrot² was implemented in 2001 by Dawid Weiss as part of his MSc thesis to validate the applicability of the STC clustering algorithm to clustering search results in Polish. In 2003, a number of other search results clustering algorithms were added, including Lingo, a novel text clustering algorithm designed specifically for clustering of search results. While the source code of Carrot² was available since 2002, it was only in 2006 when version 1.0 was officially released. In the same year, version 2.0 was released with improved user interface and extended tool set. In 2009, version 3.0 brought significant improvements in clustering quality, simplified API and new GUI application for tuning clustering based on the Eclipse
Rich Client Platform. In 2020, version 4.0.0 brought further simplification of the API, code cleanups and removal of the desktop Workbench. Version 4.1.0 brings back the Workbench as a web-based application. == Architecture ==