diff --git a/javatests/google/registry/flows/FlowTestCase.java b/javatests/google/registry/flows/FlowTestCase.java
index 12e0858f3..d6920d16e 100644
--- a/javatests/google/registry/flows/FlowTestCase.java
+++ b/javatests/google/registry/flows/FlowTestCase.java
@@ -83,6 +83,7 @@ public abstract class FlowTestCase<F extends Flow> extends ShardableTestCase {
   @Rule
   public final AppEngineRule appEngine = AppEngineRule.builder()
       .withDatastore()
+      .withMemcache()
       .withTaskQueue()
       .build();
 
diff --git a/javatests/google/registry/testing/AppEngineRule.java b/javatests/google/registry/testing/AppEngineRule.java
index 8a0f4343a..404e9a12b 100644
--- a/javatests/google/registry/testing/AppEngineRule.java
+++ b/javatests/google/registry/testing/AppEngineRule.java
@@ -21,6 +21,7 @@ import static java.nio.charset.StandardCharsets.UTF_8;
 import static org.json.XML.toJSONObject;
 
 import com.google.appengine.tools.development.testing.LocalDatastoreServiceTestConfig;
+import com.google.appengine.tools.development.testing.LocalMemcacheServiceTestConfig;
 import com.google.appengine.tools.development.testing.LocalModulesServiceTestConfig;
 import com.google.appengine.tools.development.testing.LocalServiceTestConfig;
 import com.google.appengine.tools.development.testing.LocalServiceTestHelper;
@@ -95,6 +96,7 @@ public final class AppEngineRule extends ExternalResource {
 
   private boolean withDatastore;
   private boolean withLocalModules;
+  private boolean withMemcache;
   private boolean withTaskQueue;
   private boolean withUserService;
   private boolean withUrlFetch;
@@ -120,6 +122,12 @@ public final class AppEngineRule extends ExternalResource {
       return this;
     }
 
+    /** Turn on the use of local modules. */
+    public Builder withMemcache() {
+      rule.withMemcache = true;
+      return this;
+    }
+
 
     /** Turn on the task queue service. */
     public Builder withTaskQueue() {
@@ -273,6 +281,9 @@ public final class AppEngineRule extends ExternalResource {
           .addBasicScalingModuleVersion("tools", "1", 1)
           .addBasicScalingModuleVersion("backend", "1", 1));
     }
+    if (withMemcache) {
+      configs.add(new LocalMemcacheServiceTestConfig());
+    }
     if (withTaskQueue) {
       File queueFile = temporaryFolder.newFile("queue.xml");
       Files.asCharSink(queueFile, UTF_8).write(taskQueueXml);
diff --git a/javatests/google/registry/testing/DatastoreHelper.java b/javatests/google/registry/testing/DatastoreHelper.java
index 37e5369ec..9b6ace72a 100644
--- a/javatests/google/registry/testing/DatastoreHelper.java
+++ b/javatests/google/registry/testing/DatastoreHelper.java
@@ -819,8 +819,10 @@ public class DatastoreHelper {
       public void vrun() {
         saveResource(resource, wantBackup);
       }});
-    // Force the session to be cleared so that when we read it back, we read from Datastore
-    // and not from the transaction cache or memcache.
+    // Force the session cache to be cleared so that when we read the resource back, we read from
+    // Datastore (or memcache) and not from the session cache. This is needed to trigger Objectify's
+    // load process (unmarshalling entity protos to POJOs, nulling out empty collections, calling
+    // @OnLoad methods, etc.) which is bypassed for entities loaded from the session cache.
     ofy().clearSessionCache();
     return ofy().load().entity(resource).now();
   }