There are versions of Shen in javascript, sbcl, ruby, java, python, scheme, clojure and haskell (http://www.shenlanguage.org/download_form.html)

The basic idea is to construct a kernel with 40 functions in such a way that the language is easily portable. With those 40 functions Shen is like a mixture of Lisp, prolog and typep racket.

I should like to see a version of Shen in Nim.