"Learning Racket" series

"Learning Racket" series An expert programmer learns Racket and takes notes in the process. Many interesting remarks, for example (after discovering a library that let the user bend the language):

It must be any language designer's ultimate dream.

(And this is probably Lisp's greatest weakness as well – with this level of possible diversity, everyone has to use the “common lowest denominator” simply because nobody can agree on what alternative syntax / library / etc. is better and should be used.)