diff --git a/src/babashka/impl/classes.clj b/src/babashka/impl/classes.clj
index 66761176..eb156066 100644
--- a/src/babashka/impl/classes.clj
+++ b/src/babashka/impl/classes.clj
@@ -268,6 +268,7 @@
                       clojure.lang.LazySeq
                       clojure.lang.Named
                       clojure.lang.Keyword
+                      clojure.lang.Ratio
                       clojure.lang.Repeat
                       clojure.lang.Symbol
                       clojure.lang.Sequential