Designing Elixir Systems With OTP

Chapter 3 Start with the Right Data Layer

This chapter will continue looking at the “D” for “data” part of “Do fun things with big, loud worker-bees.” We’ll use the Elixir datatypes you saw in the previous chapter to roll up data structures. Elixir is a functional programming language and that concept will have a huge impact on how you represent data. In functional programming, functions can’t update data in place, they must create new copies that transform data step by step. When your data structures are wrong, your code must compensate and will in turn not only look awkward but also just feel wrong. The following figure shows that your data layer often serves as the foundation:

In the sections that follow, we’ll explore how your foundational ...