diff --git a/pom.xml b/pom.xml
index 593aa4e..18185ec 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,7 +5,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>net.helenus</groupId>
     <artifactId>helenus-core</artifactId>
-    <version>2.0.36-SNAPSHOT</version>
+    <version>2.0.38-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <name>helenus</name>
diff --git a/src/main/java/net/helenus/core/UnitOfWork.java b/src/main/java/net/helenus/core/UnitOfWork.java
index 8635f43..c947c12 100644
--- a/src/main/java/net/helenus/core/UnitOfWork.java
+++ b/src/main/java/net/helenus/core/UnitOfWork.java
@@ -52,14 +52,14 @@ public class UnitOfWork<T extends Exception> implements AutoCloseable {
   }
 
   public Set<Object> cacheLookup(String key) {
-    UnitOfWork<T> p = this;
-    do {
-      Set<Object> r = p.getCache().get(key);
-      if (r != null) {
-        return r;
+    Set<Object> r = getCache().get(key);
+    if (r != null) {
+      return r;
+    } else {
+      if (parent != null) {
+        return parent.cacheLookup(key);
       }
-      p = parent;
-    } while(p != null);
+    }
     return null;
   }
 
diff --git a/src/main/java/net/helenus/core/operation/AbstractOptionalOperation.java b/src/main/java/net/helenus/core/operation/AbstractOptionalOperation.java
index f4bf79b..8083785 100644
--- a/src/main/java/net/helenus/core/operation/AbstractOptionalOperation.java
+++ b/src/main/java/net/helenus/core/operation/AbstractOptionalOperation.java
@@ -23,7 +23,6 @@ import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 
 import java.util.HashSet;
-import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.CompletableFuture;