Hello, cffi-devel! Sorry, last message was messed by gpg. I have found a case when cffi behaves not as documented. The documentation in page for define-foreign-library says about load-clauses list that "Finally, if feature is t, this load-clause is picked unconditionally." But the load-clause with feature set to T is ignored, because function %foreign-library-spec uses alexandria:featurep, which does consider T to be feature. This patch should fix this: to return the load-clause that has feature set to T. Test case: (define-foreign-library libgraphan-wrap (t (:default "libgraphan-wrap"))) (equal (%foreign-library-spec (get-foreign-library 'libgraphan-wrap)) (t (:default "libgraphan-wrap"))) => T