Fix deadlock on missing assets directory.
diff --git a/find.lisp b/find.lisp
index 03c443e..02b062d 100644
--- a/find.lisp
+++ b/find.lisp
@@ -96,7 +96,9 @@
:initial-value assets))
(defmethod find-assets (type (dir null) name ext assets)
- (find-assets type (assets-dirs) name ext assets))
+ (let ((dir (assets-dirs)))
+ (when dir
+ (find-assets type dir name ext assets))))
;; Resolve class