(ql:quickload :nibbles)
(load (compile-file "~/test.lisp"))
(foo (make-vector-input (make-array 4 :element-type '(unsigned-byte 8) :initial-contents '(1 2 3 4)) 0))

;; => The function NIBBLES::%UB32REF/LE is undefined.

;; And yet:
(nibbles:ub32ref/le (make-array 4 :element-type '(unsigned-byte 8) :initial-contents '(1 2 3 4)) 0)
;; => 67305985