This is a minor nitpick but I feel that the usage of the arrow function in Javascript was overly verbose.

Instead of:

  const add = (a, b) => {
    return a + b;
  }

It could be written as:

  const add = (a, b) => a + b

Or functions can also easily be turned into curried functions by doing:

  const add = a => b => a + b

Which can be really powerful when used properly.

I felt it was worth mentioning, but I understand that the goal of the article was not to provide a in-depth comparison.