Lucene Solr is an open source technology and community that has proved its worth in heavy hitting applications inside platform companies like LinkedIn and Zappos.

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According to Ingersoll, Twitter search is powered by Lucene, handling more than a billion queries a day, with close to four hundred million tweets indexed and available within 50 milliseconds of being posted (see here for a 2010 post about Lucene by the Twitter engineering team).

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