From homepage:

Hy (or "Hylang" for long) is a multi-paradigm general-purpose programming language in the Lisp family. It's implemented as a kind of alternative syntax for Python. Compared to Python, Hy offers a variety of new features, generalizations, and syntactic simplifications, as would be expected of a Lisp. Compared to other Lisps, Hy provides direct access to Python's built-ins and third-party Python libraries, while allowing you to freely mix imperative, functional, and object-oriented styles of programming. (More on "Why Hy?")

Some examples on the homepage:

Hy:

 hy

    
(defmacro do-while [test #* body]
  `(do
    ~@body
    (while ~test
      ~@body)))

(setv x 0)
(do-while x
  (print "Printed once."))

  

Python:

 python

    
x = 0
print("Printed once.")
while x:
    print("Printed once.")


  

Interestingly programming.dev's Markdown renderer highlights hy code blocks. Maybe it knows the language (highlight.js has it). Maybe it's using Hybris (another language that could get its own post, one of its extensions is *.hy).

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