Racket is a general-purpose programming language as well as the world's first ecosystem for developing and deploying new languages. – Racket (by The Racket Manifesto).

Racket

Batteries included –Racket's extensive standard library gets your projects off the ground quickly.

Cross-platform –Racket runs on Linux, macOS, and Windows. Develop on one; deploy to all three.

Powerful macros & languages –Racket's crown jewel is its macro system, which lets you freely extend the language.

Mature, stable, open source – Racket is a mature LGPL project that's actively developed and maintained.

DrRacket IDE & tons of documentation –DrRacket is a graphical IDE that's integrated with Racket's vast documentation.

The best of Scheme and Lisp –Racket started life as a Scheme implementation, but then grew into new areas.

The principles of Racket

1. Racket is about creating new programming languages quickly.
2. Racket provides building blocks for strong protection mechanisms.
3. Racket turns extra-linguistic mechanisms into linguistic constructs

(From The Principles of Racket.)