I'm surprised: the language is very straightfoward, simple, very few rules to remember. It's a Lisp but with a very small surface area.
I mean, compared to other languages, Janet really is easier to lean, so I'm surprised that the book for it is difficult (did not read the book, but familiar-ish with the language. I don't have anything but praise for it, TBH).
I had that with Haskell. Although, while Haskell is too hard for me, I actually like its syntax.
Janet seems to be Lisp 2.0, so the syntax is lispy.