diff --git a/src/main/java/org/embeddedt/modernfix/classloading/FastAccessTransformerList.java b/src/main/java/org/embeddedt/modernfix/classloading/FastAccessTransformerList.java
index 8e83b325..3d435320 100644
--- a/src/main/java/org/embeddedt/modernfix/classloading/FastAccessTransformerList.java
+++ b/src/main/java/org/embeddedt/modernfix/classloading/FastAccessTransformerList.java
@@ -49,8 +49,9 @@ public class FastAccessTransformerList extends AccessTransformerList {
         private final Set<Type> allContainedTypes;
 
         public FastATMap(Map<Target<?>, AccessTransformer> delegate) {
-            this.delegate = delegate;
+            this.delegate = new HashMap<>();
             this.allContainedTypes = new ObjectOpenHashSet<>();
+            this.putAll(delegate);
         }
 
         @Override