The book Real-Time Phoenix is good for designing realtime systems. For a good introduction to Elixir, I loved Elixir in Action which also covers OTP. If you w

The book Real-Time Phoenix is good for designing realtime systems. For a good introduction to Elixir, I loved Elixir in Action which also covers OTP. If you want a good Phoenix resource, the book Programming Phoenix is good. Finally, the docs in Elixir and Phoenix are great.