[rossj]

I guess one difference is the approach to concurrency. Node is still (as far as I am aware) single thread per process, and so tends to take the approach of using multiple processes (so that multiple cores are used) and some form of IPC.

Elixir (because Erlang) handles the distributing of 'processes' (not operating system processes but Erlang lightweight process) across cores for you. Erlang's been doing concurrency for a long time, it's very good at it.

The style of programming is very different in that you are encouraged to use processes in Elixir, rather than the callback style that is prevalent in Node. It feels weird at first, but pretty natural after a while.

I'm not sure there's much you can do in Node that you can't do in Elixir. But there are features in Elixir (again, because Erlang) like hot-code-reloading (update your app whilst it is running), and the way it can distribute tasks across nodes that I'm not sure are that straight-forward with Node.