So far, we have run our PaaS on a single host, which can be a problem if we need to scale out. There is a lot happening in this space, and I have selected a few projects that I will introduce in this chapter. These projects vary a lot in how mature they are, one is ready for use in production while the other is in a prototype state. In this chapter, we will cover the following topics:
Many of today's apps are, in fact, web apps that you run in your web browser. Gmail, Slack, Wunderlist, Trello, and so on are all web apps or software-as-a-service.
It is these kind of apps that are suitable to be run on a PaaS.
The Twelve-Factor app is ...