Agreed! I taught myself programming, and Haskell was my second language. I was at Penn so I emailed Brent out of the blue, and he responded and was so helpful with understanding helping me understand Monoids, not at all judgmental, and so different from all the educational experience I had up until then. And it was serious gateway drug to mathmatics. Funny thing is a few years later I TAed an advanced Haskell class with Stephanie Weirich (https://www.seas.upenn.edu/~cis552/current/index.html), who was Brent's thesis advisor. All started with Brent!