Since the start of Google’s App Engine for Java, I have tried to create a small but representative project and to deploy it on Google’s infrastructure. I have learned much, mainly by making mistakes. Interestingly enough, there are much that I achieved I didn’t hope I would. On the contrary, the Devil is in the details, as they say, and I found some problems I couldn’t imagine there: for some, there are other solutions, for some, there aren’t.