Lisp: If on Guix, load CFFI and add ~/.guix-profile/lib to CFFI's load path

.sbclrc

@@ -8,3 +8,13 @@
                                        (user-homedir-pathname))))
   (when (probe-file quicklisp-init)
     (load quicklisp-init)))
+
+;; Some OSes package Lisp compilers in a way that ASDF is not automatically loaded.
+(require "asdf")
+
+(let ((guix-profile (format nil "~a/.guix-profile/lib/" (uiop:getenv "HOME"))))
+  (when (and (probe-file guix-profile)
+             (ignore-errors (asdf:load-system "cffi")))
+    (push guix-profile
+          (symbol-value (find-symbol (string '*foreign-library-directories*)
+                                     (find-package 'cffi))))))