diff --git a/README b/README
index 88643d6..7d8712b 100644
--- a/README
+++ b/README
@@ -33,6 +33,10 @@ the current directory to ASDF's registry is
 	(push *default-pathname-defaults* asdf:*central-registry*)
 	(asdf:load-system :ham)
 
+As it stands the system will only work with SBCL, though I don't think
+it would be *that* much work to get it working with other Common Lisp
+implementations.
+
 Maxima ended up being a bit of a pain to build fully within ASDF so
 the ASDF config first compiles it with its autotools set-up (so you'll
 need autoconf et al) and uses the FASLs from that build when possible.