If you like this work you'll also like Typed Racket, on which it is based. Sam TH is the main author and his publications are here: http://www.ccs.neu.edu/home/samth/
The first thing I thought of while opening this article was Qi / Shen, an optionally typed Lisp which takes inspiration from the ML family of languages. http://www.shenlanguage.org/
Shen's dedication to providing functional concepts such as partial application really interests me, but I find Clojure's practical nature even more enticing. Perhaps Typed Racket and this type system for Clojure will provide the best of both worlds!
Shen is pretty amazing and is built with a type system in mind from the beginning. If you don't want the type system, just turn it off, in the middle of a REPL session if you want!
Shen's dedication to providing functional concepts such as partial application really interests me, but I find Clojure's practical nature even more enticing. Perhaps Typed Racket and this type system for Clojure will provide the best of both worlds!