Elixir and Phoenix are generating tremendous excitement as an unbeatable platform for building modern web applications For decades OTP has helped developers create incredibly robust, scalable applications with unparalleled uptime Make the most of them as you build a stateful web app with Elixir, OTP, and Phoenix Model domain entities without an ORM or a database Manage server state and keep your code clean with OTP Behaviours Layer on a Phoenix web interface without coupling it to the business logic Open doors to powerful new techniques that will get you thinking about web development in fundamentally new ways Elixir and OTP provide exceptional tools to build rock solid back end applications that scale In this book, you ll build a web application in a radically different way, with a back end that holds application state You ll use persistent Phoenix Channel connections instead of HTTP s request response, and create the full application in distinct, decoupled layers In Part , start by building the business logic as a separate application, without Phoenix Model the application domain with Elixir functions and simple data structures By keeping state in memory instead of a database, you can reduce latency and simplify your code In Part , add in the GenServer Behaviour to make managing in memory state a breeze Create a supervision tree to boost fault tolerance while separating error handling from business logic Phoenix is a modern web framework you can layer on top of business logic while keeping the two completely decoupled In Part , you ll do exactly that as you build a web interface with Phoenix Bring in the application from Partas a dependency to a new Phoenix project Then use ultra scalable Phoenix Channels to establish persistent connections between the stateful server and a stateful front end client You re going to love this way of building web appsWhat You NeedYou ll need a computer that can run Elixir versionor higher and Phoenixor higher Some familiarity with Elixir and Phoenix is recommended