I loved reading that part! I've always found ocaml's (and now rescript's) first class modules flexible and powerful. They're definitely awkward but in that way where you're having to explicitly think about and declare relationships you'd happily ignore until they bite you.

Recently I've seen a lot of programmers I respect consider them a weaker or failed alternative to typeclasses, basically a dead-end. And I had been reluctantly coming to the conclusion that I must be wrong in some way I'm not able to fully perceive yet. Seeing such a notable PL designer come out on their side makes me feel less like a fool.