```
diff --git a/core/src/main/java/org/jruby/ext/timeout/Timeout.java b/core/src/main/java/org/jruby/ext/timeout/Timeout.java
index 9d8b7dd4e7..a67e62eb82 100644
--- a/core/src/main/java/org/jruby/ext/timeout/Timeout.java
+++ b/core/src/main/java/org/jruby/ext/timeout/Timeout.java
@@ -69,7 +69,7 @@ public class Timeout {
         executor.setRemoveOnCancelPolicy(true);
         timeout.setInternalVariable(EXECUTOR_VARIABLE, executor);
 
-        timeout.getRuntime().pushExitFunction((context) -> { executor.shutdown(); return 0;});
+        timeout.getRuntime().addInternalFinalizer(executor::shutdown);
     }
 
 

```