Fast-stemmer is simply a wrapping around multithreaded Porter stemming algorithm. This gem adds a String#stem method, and it conflicts with the stemmer gem. It's in order of magnitude faster (and uses much less memory) than the latter. For the original work please see: http://tartarus.org/~martin/PorterStemmer/ Gemfile: gem 'fast-stemmer' Usage: require 'rubygems' require 'fast_stemmer' Stemmer::stem_word('running') # -> 'run' 'running'.stem # -> 'run' COPYRIGHT ========= Copyright (c) 2008 Roman Shterenzon. See LICENSE for details.