If one is acquainted to Scheme, it's better skimming through the introduction for an overview of all the language features.

https://cons.io/guide/intro.html

Seeing it has objects, methods structs, optional type annotation, couroutines, actor model, I tried to build it but the Gambit Scheme on my system was too old and I gave up.

Also an older but still useful overview of all the Schemes when used for scientific computing:

http://fmnt.info/blog/20181029_scheme.html