This talk will describe some of the engineering approaches behind CityVille by Zynga, which became the #1 game on Facebook within weeks of its release. We will take a look at the server-side engineering that allowed us to grow rapidly, as well as gameplay engineering that let us rapidly build great gameplay features for our players. The talk will evaluate new innovations and departures from the past, as well as tried-and-true techniques that were successfully adopted to a new title in a new setting.