This is written for someone who is already a programmer and familiar with two or three programming languages. For someone new to programming, the route proposed here might not work.

Do I need to learn Erlang?

Yes, Although you might not write lot of Erlang code, you need to be able to read Erlang code and browse through the Erlang documentation to figure out the details.

Elixir differs from the mainstream languages in three main aspects.

Immutability

Values in Elixir are immutable, it can’t be changed in-place. This kind of trips up a lot of programmers who are used to c or Java where the predominant style is to mutate values in-place.

Concurrency

Most of the languages support shared state concurrency. Multiple threads will share a common state and they communicate with each other by mutating the state in-place. The actor model approach taken by Elixir is completely different from this model.

Macro

None of the mainstream languages supports macro. Unless you already know any Lisp-like language, you might not have much idea about what is macro and how it’s useful.

Trying to learn all the three aspects of the language at the same time might not work out for everyone. The easy way is to learn them one by one.

The getting started guide provides a nice introduction to the language tools and syntax. Read the first 22 chapters. Depending on your background, by the time you finish this, you would be able to write useful programs in Elixir.

Learn You Some Erlang is a great book. The first part of the book focus on the functional aspect of the language, the rest of the book focus on the concurrency part.

Elixir in Action is another great book. Most of the material covered here is already covered by Learn You Some Erlang, but it’s nice to go through them once again and understand how the Erlang code maps to Elixir code.

Macro is something which you would not use in everyday programming. But it’s invaluable in some situations. I could not find any good introductory book on macros in Elixir. The best way I could find is to read On Lisp or Let Over Lambda. Once you understood it’s use cases, you can read the Meta Programming section in getting started guide and also read the Metaprogramming Elixir book.

Making reliable distributed systems in the presence of software errors is written by Joe Armstrong. It explains the reason for some of the language design decisions and provides advice on how to organize large-scale projects.

Erlang in Anger is written by the same guy who wrote Learn You Some Erlang. It explains how to debug or find problems in production systems. It’s worth a skim through.