ASDF and Exports and CLisp

I am curious, what are your thoughts on exposing functions and handling multiple lisp modules that require the use of functions from other files.

'package.lisp'?

(:export #:define-test #:run-all-tests #:run-tests ...

Right now, I just have one file, and doing :export ... and defining as many functions as I can. but I probably forget to reference half of them. Sometimes I get warnings and sometimes I get errors. My question, is there a way to force an error or something if the function exposed?
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