In this section, we will build the source code for our microservice. In order to do so, in addition to the prerequisites described previously, you will need PostgreSQL installed on your system. As I mentioned earlier, we will use Docker to install and handle PostgreSQL. I'm using a macOS High Sierra as my working environment. If you have implemented the same project using Thorntail (as described in Chapter 4, Building Microservices Using Thorntail, feel free to skip this section; otherwise, follow the instructions that describe how to install and run PostgreSQL in a Docker container.