The turnstile language “[…]aims to help Racket programmers create typed languages. It does so with extensions of Racket’s macro-definition forms that facilitate implementation of type rules alongside normal macro code.”

https://docs.racket-lang.org/turnstile/ @mario.luis.guimaraes

That one is something to look at indeed. Thanks @spdegabrielle

@mario.luis.guimaraes also check out the blog posts https://lexi-lambda.github.io/tags/hackett.html

maybe this on specifically https://lexi-lambda.github.io/blog/2018/04/15/reimplementing-hackett-s-type-language-expanding-to-custom-core-forms-in-racket/

I am aware of Hackett, and it is something to learn from also.

good luck - I’d love to hear about your language and type system implementation efforts!

Oh, I am slowly entering this world of making a progamming languages, without hurry. I just have random ideas of what I would like to have, which as I progress and learn more, may well change. But the principal idea is that of a statically typed Lisp, much in the vein of things like Hackett and Clasp. It may be the case that one day one of these may fullfil what I look for in a programming language; maybe none of these will, and I’ll look into something else. Just now I have other projects, but following with interest new programming languages, especially statically typed.