diff --git a/src/babashka/impl/classes.clj b/src/babashka/impl/classes.clj
index b599f9f4..d964e851 100644
--- a/src/babashka/impl/classes.clj
+++ b/src/babashka/impl/classes.clj
@@ -509,6 +509,7 @@
           java.util.concurrent.CompletionStage
           java.util.concurrent.locks.ReentrantLock
           java.util.concurrent.ThreadLocalRandom
+          java.util.concurrent.ConcurrentHashMap
           java.util.jar.Attributes
           java.util.jar.Attributes$Name
           java.util.jar.JarFile