Exactly, Erlang is a highly concurrent distributed system out of the box but this does not mean too much for Rails developers, on the other side the syntax is kind of hard to get used to. I think this is primarily why Elixir was created. I think if we see the usage or Erlang in the world it has enough momentum already and it proved itself with empowering startups like WhatsApp. On the top of that, the Erlang community is absolutely amazing. I guess I don't understand what the author means in terms of momentum. Is Erlang popular on Github? Certainly not. Should we use this to measure momentum? I don't think so.