[1]: The book is free as well: https://mitpress.mit.edu/sicp/full-text/book/book-Z-H-4.html...
SICP being freely available in both book form, and the lectures [0] makes it one of the best resources out there.
(I just never found it's section on compilers that helpful. Again, probably learning styles.)
[0] https://www.youtube.com/playlist?list=PLB63C06FAF154F047