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Just a curious question. When I type a question in stackoverflow, suggestions come up which shows similar questions. This clearly indicates there is a searching and ranking procedure going in behind. I was wondering which search technology stackoverflow uses under the interface, is it lucence, Sphinx, Terrier or any other?

marked as duplicate by Austin Henley, Lance Roberts, Mat, Rory, Martijn Pieters Feb 27 '13 at 12:14

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