How do you know what 100 millions users like? Wix.com is conducting hundreds of experiments per month on production to understand which features our users like and which hurt or improve our business. At Wix we have developed our 3rd generation experiment system called Petri, which was open sourced. Petri helps us maintain some order in a chaotic system that keeps changing. We will also explain how it works and what are the patterns in conducting experiments that have a minimal effect on performance and user experience.
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