Oddly enough most of the startups around where I am at have been based on Rails. Some people use Node as well. That’s about as $hype_of_the_year as it gets here.
Node.js is 9 years old and is also very stable with a large ecosystem. It's far from "hype train" in 2018 and it's more the mature technology - though it's still moving fast forward with new tools and paradigms it's very stable.
