It works for Schemes that DrRacket supports or ones implemented via #lang. I don't think Chez Scheme is one of those.

There's actually a plugin that lets one use Chez directly from DrRacket.

Got a link?

I used the plugin to run the Chez version of minikanren some time ago. I think it was this one:

https://github.com/Syntacticlosure/chez-runner

There might be more on the racket package server.

Last time I checked, it didn't have true REPL development ? i.e you couldn't "just eval" a function ?

DrRacket has had a REPL at least since 2013 (which was when I first used it).

I think the commenter meant sending a specific function definition to the REPL, like in Common Lisp, Clojure, or F#'s REPLs, without re-evaluating the entire file, like how DrRacket does it. I think Racket has some functionality that allows it though, and I think the Racket Emacs mode supports it. I am not aware of how to do it with DrRacket.

Yes exactly ! Sory for confusion.