Cloud solutions, and specifically the Google App Engine, are designed for scalability and flexible usage from scratch. However, in the case of the Google App Engine, this design may mean that some classic performance optimization strategies are counterproductive. This chapter focused on cold startup time and why you should avoid cold startups when possible. It also discussed the overhead of frameworks and libraries—also to be avoided when possible. The end of this chapter presented a few performance questions with cross references to the chapters where you can find the answers.