diff --git a/src/main/java/net/openhft/chronicle/hash/replication/ReplicationChannel.java b/src/main/java/net/openhft/chronicle/hash/replication/ReplicationChannel.java
index 13d883e56..29ae03377 100644
--- a/src/main/java/net/openhft/chronicle/hash/replication/ReplicationChannel.java
+++ b/src/main/java/net/openhft/chronicle/hash/replication/ReplicationChannel.java
@@ -20,6 +20,8 @@ import net.openhft.chronicle.hash.ChronicleHash;
 import net.openhft.chronicle.hash.ChronicleHashInstanceConfig;
 import org.jetbrains.annotations.NotNull;
 
+import java.io.Serializable;
+
 /**
  * A token which should be created via {@link ReplicationHub#createChannel(int)} call and passed to {@link
  * ChronicleHashInstanceConfig#replicatedViaChannel(ReplicationChannel)} method, to establish a channel
@@ -31,7 +33,7 @@ import org.jetbrains.annotations.NotNull;
  * @see ReplicationHub
  * @see ReplicationHub#createChannel(int)
  */
-public final class ReplicationChannel {
+public final class ReplicationChannel implements Serializable{
     private ReplicationHub hub;
     private final int channelId;
 
diff --git a/src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java b/src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java
index bb0a72da2..ebf938d2c 100755
--- a/src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java
+++ b/src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java
@@ -99,7 +99,7 @@ import static net.openhft.lang.model.DataValueGenerator.firstPrimitiveFieldType;
  * @see ChronicleSetBuilder
  */
 public final class ChronicleMapBuilder<K, V> implements Cloneable,
-        ChronicleHashBuilder<K, ChronicleMap<K, V>, ChronicleMapBuilder<K, V>> {
+        ChronicleHashBuilder<K, ChronicleMap<K, V>, ChronicleMapBuilder<K, V>>, Serializable {
 
     static final byte UDP_REPLICATION_MODIFICATION_ITERATOR_ID = (byte)128;
     private static final int DEFAULT_KEY_OR_VALUE_SIZE = 120;
diff --git a/src/main/java/net/openhft/chronicle/map/MapInstanceConfig.java b/src/main/java/net/openhft/chronicle/map/MapInstanceConfig.java
index e6dd4eab5..67959f6a8 100644
--- a/src/main/java/net/openhft/chronicle/map/MapInstanceConfig.java
+++ b/src/main/java/net/openhft/chronicle/map/MapInstanceConfig.java
@@ -23,10 +23,11 @@ import net.openhft.chronicle.hash.replication.TcpTransportAndNetworkConfig;
 
 import java.io.File;
 import java.io.IOException;
+import java.io.Serializable;
 import java.util.concurrent.atomic.AtomicBoolean;
 
 final class MapInstanceConfig<K, V>
-        implements ChronicleHashInstanceConfig<ChronicleMap<K, V>> {
+        implements ChronicleHashInstanceConfig<ChronicleMap<K, V>>, Serializable{
 
     final ChronicleMapBuilder<K, V> mapBuilder;
     final SingleChronicleHashReplication singleHashReplication;
diff --git a/src/main/java/net/openhft/chronicle/map/ReplicationHubFindByName.java b/src/main/java/net/openhft/chronicle/map/ReplicationHubFindByName.java
index b0775d846..92d5d9d86 100644
--- a/src/main/java/net/openhft/chronicle/map/ReplicationHubFindByName.java
+++ b/src/main/java/net/openhft/chronicle/map/ReplicationHubFindByName.java
@@ -27,7 +27,6 @@ import org.slf4j.LoggerFactory;
 
 import java.io.File;
 import java.io.IOException;
-import java.io.Serializable;
 import java.util.Map;
 import java.util.concurrent.TimeoutException;
 import java.util.concurrent.atomic.AtomicInteger;
@@ -83,7 +82,7 @@ class ReplicationHubFindByName<K> implements FindByName {
 
         this.map = (Map) ChronicleMapBuilder
                 .of(CharSequence.class, MapInstanceConfig.class)
-                .entrySize(3000)
+                .entrySize(4000)
                 .entries(128)
                 .eventListener(listener)
                 .instance()
diff --git a/src/test/java/net/openhft/chronicle/map/EntryCountMapTest.java b/src/test/java/net/openhft/chronicle/map/EntryCountMapTest.java
index 0129f5048..1842c9d4b 100644
--- a/src/test/java/net/openhft/chronicle/map/EntryCountMapTest.java
+++ b/src/test/java/net/openhft/chronicle/map/EntryCountMapTest.java
@@ -137,7 +137,7 @@ public class EntryCountMapTest {
     }
 
     @Test
-    @Ignore
+    @Ignore ("ignore because its a scalability test")
     public void testLarge() throws Exception {
         int s = 8 * 1024;
         for (int i = 0; i < 10; i++) {
diff --git a/src/test/java/net/openhft/chronicle/map/MapByNameTest.java b/src/test/java/net/openhft/chronicle/map/MapByNameTest.java
index 2859031f6..8be61bd82 100644
--- a/src/test/java/net/openhft/chronicle/map/MapByNameTest.java
+++ b/src/test/java/net/openhft/chronicle/map/MapByNameTest.java
@@ -16,7 +16,6 @@
 
 package net.openhft.chronicle.map;
 
-import net.openhft.chronicle.hash.ChronicleHashInstanceConfig;
 import net.openhft.chronicle.hash.replication.ReplicationHub;
 import net.openhft.chronicle.hash.replication.TcpTransportAndNetworkConfig;
 import org.junit.Before;
@@ -46,17 +45,17 @@ public class MapByNameTest {
     }
 
     @Test
-    @Ignore("builder is not serializable")
     public void testSerializingBuilder() throws TimeoutException, InterruptedException, IOException {
 
         final MapInstanceConfig<CharSequence, CharSequence> config =
                 (MapInstanceConfig<CharSequence, CharSequence>)
-                ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
-                .entries(2)
-                .minSegments(2)
-                .replication((byte) 1, TcpTransportAndNetworkConfig.of(8244))
-                .removeReturnsNull(true)
-                .instance().name("map1");
+                        ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
+                                .entrySize(900)
+                                .entries(2)
+                                .minSegments(2)
+                                .replication((byte) 1, TcpTransportAndNetworkConfig.of(8244))
+                                .removeReturnsNull(true)
+                                .instance().name("map1");
 
         final ChronicleMap<CharSequence, CharSequence> map = findMapByName.create(config);
         map.put("hello", "world");
@@ -77,11 +76,11 @@ public class MapByNameTest {
 
         MapInstanceConfig<CharSequence, CharSequence> config =
                 (MapInstanceConfig<CharSequence, CharSequence>)
-                ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
-                .minSegments(2)
-                .removeReturnsNull(true)
-                .instance()
-                .name("myMap");
+                        ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
+                                .minSegments(2)
+                                .removeReturnsNull(true)
+                                .instance()
+                                .name("myMap");
 
         ReplicationHubFindByName<CharSequence> mapByName = nodeDiscovery.mapByName();
         //  mapByName.add(config);
@@ -97,12 +96,12 @@ public class MapByNameTest {
 
         MapInstanceConfig<CharSequence, CharSequence> config =
                 (MapInstanceConfig<CharSequence, CharSequence>)
-                ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
-                .minSegments(2)
-                .entries(2)
-                .removeReturnsNull(true)
-                .instance()
-                .name("myMap6");
+                        ChronicleMapBuilder.of(CharSequence.class, CharSequence.class)
+                                .minSegments(2)
+                                .entries(2)
+                                .removeReturnsNull(true)
+                                .instance()
+                                .name("myMap6");
 
         ChronicleMap<String, String> map = mapByName.create(config);
         map.put("hello", "world");