[racket] Preferred business rules engines in or used by Racket?

Hi,

May you please share your experience or preferences for rules engines
written in or used from Racket?

My goal is to:

1. Allow rule definitions separate from the code (though I view rule
definitions as programming to be performed by the programmer).
2. Allow rules to be defined in modules.
3. Provide debugging features such that I may sit with a business
user, and start with a particular scenario of data, and walk them
through how the rules transform the data. The goal is to be able to
answer questions from the business eg "I didn't expect this result,
why is it this way?.
4. Debugging.
5. Nice editing.
6. Find something nice for 3-9 month projects with 2-4 developers; in
other words not looking for an enterprise system with licensing priced
accordingly.
7. Any technology is an option because we can probably use it with
some form of interop.
8. Find something that people use for real work for a long time.
9. Find something that costs not more than a thousand USD.
10. Find something that changes how you think, has materials to help
change that, and gets you down the path of thinking about how to write
system with rules engines rather than shoe-horn them into a corner.

Best wishes,

Grant

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