In this chapter, we started working on the application stack and deploying real things on Swarm. We did some practice in defining Swarm services and we launched a cluster of nginx, as well as a load-balanced WordPress on a dedicated overlay network. Then, we moved on to something more real: Apache Spark. We deployed Spark on Swarm at a small scale, by defining our own scheduling strategies. We are going to expand Swarm and scale it to a bigger size, with more real storage and networking options, in Chapter 7, Scaling Up Your Platform.