The functional core can return a symbolic description of actions to take, which the shell executes, a bit like a simple interpreter. This is a good example: h

The functional core can return a symbolic description of actions to take, which the shell executes, a bit like a simple interpreter. This is a good example: https://www.theerlangelist.com/article/spawn_or_not https://www.theerlangelist.com/article/spawn_or_not (Note the context is Elixir, so it’s talking about lightweight processes, not OS processes. It explains how to keep that stateful / effectful code very simple, and have all the real logic be pure functional code.)