Flexible metaprogramming with Rhombus

Rhombus is a new programming language that combines Racket's advanced metaprogramming capabilities with Python-like syntax and more efficient default data structures, aiming to make powerful programming techniques accessible beyond academic circles. The language, which reached version 1.0 in June 2026, is developed by the Racket Programming Language Foundation and already includes real-world applications like tools for the Economancy card game. Rhombus features distinctive syntax elements such as indentation-based blocks and reducers in for loops that allow operations like list comprehensions and mathematical aggregations directly within loop constructs.