This is great. I'm learning Rust myself and your son's article contributed to my knowledge.

I'm also very impressed by part 2. I have my own lisp but I haven't managed to implement a compiler or code generation yet. Really enjoyed reading about the hashmap too. The textbook solution to collisions is probing and comparison. It never occurred to me that I could just resize the underlying array until the collisions disappear altogether.

Very impressive for a 17yo!

17? You should be very proud. This is good work for anyone, but especially at his age!