Part 1: https://tech.buzzfeed.com/scalable-request-handling-an-odyssey-part-1-d91a295af4d8
Part 2: https://tech.buzzfeed.com/scalable-request-handling-an-odyssey-part-2-ad2433b2f6ed
Part 3: https://tech.buzzfeed.com/scalable-request-handling-an-odyssey-part-3-c29aac9c39a