There's a lot to know about Docker! If you're curious about how this project works, or want to dive deeper into Docker, check out the following two (free!) resources.
If you're unfamiliar with Docker, try out this Docker in Development course, which explains important topics in how this is put together.
If you want to see how this workflow was developed, check out the Dockerized App course, which explains how the workflow used with Vessel was created. This is a free course module from the full Shipping Docker course.