Lookout! Growing Pains was originally presented at Lookout's Scaling for Mobile event on July 25, 2013. Kyle Barton is a Senior Software Engineer at Lookout, Inc. Kyle's talk focused on the growing pains that Lookout has faced as we've scaled and engaged more users. Lookout has grown immensely in the last year. We've doubled the size of the company—added more than 80 engineers to the team, support 45+ million users, have over 1000 machines in production, see over 125,000 QPS and more than 2.6 billion requests/month. Our analysts use Hadoop, Hive, and MySQL to interactively manipulate multibillion row tables. With that, there are bound to be some growing pains and lessons learned.