I’ve never used Ruby, but at least from a Python perspective, the main difference between Elixir/BEAM and those languages is that the BEAM VM is designed to be effectively started once and never restarted, and it can use all the cores of a machine without needing to spawn new OS-level processes to maintain responsiveness.
So, the main mental leap you have to do is:
Trust the VM: It will not crash, it will not leak memory, it will not block.
