Cannot recommend Ramda enough. It's a great utility belt to build your application with. Only downside is the pushback I always receive from the team when I try to introduce it.
Reading the insightful comments in this post, I see why accommodating JavaScript's inherent flaws has snowballed web development. You need to know concepts like tree-shaking (removal of dead code) to pick among 10 different libraries that mostly do the same in subtly different ways.