diff --git a/src/main/java/com/amazonaws/services/kinesis/clientlibrary/lib/worker/Worker.java b/src/main/java/com/amazonaws/services/kinesis/clientlibrary/lib/worker/Worker.java
index 1ce25579..8f4140a1 100644
--- a/src/main/java/com/amazonaws/services/kinesis/clientlibrary/lib/worker/Worker.java
+++ b/src/main/java/com/amazonaws/services/kinesis/clientlibrary/lib/worker/Worker.java
@@ -35,6 +35,7 @@ import java.util.concurrent.TimeoutException;
 import com.amazonaws.services.kinesis.clientlibrary.proxies.IKinesisProxy;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import lombok.Getter;
 
 import com.amazonaws.regions.Region;
 import com.amazonaws.regions.RegionUtils;
@@ -1063,6 +1064,7 @@ public class Worker implements Runnable {
     /**
      * Builder to construct a Worker instance.
      */
+    @Getter
     public static class Builder {
 
         private IRecordProcessorFactory recordProcessorFactory;
@@ -1267,7 +1269,7 @@ public class Worker implements Runnable {
                 }
             }
             if (metricsFactory == null) {
-                metricsFactory = getMetricsFactory(cloudWatchClient, config);
+                metricsFactory = Worker.getMetricsFactory(cloudWatchClient, config);
             }
             if (shardPrioritization == null) {
                 shardPrioritization = new ParentsFirstShardPrioritization(1);
diff --git a/src/test/java/com/amazonaws/services/kinesis/clientlibrary/lib/worker/WorkerTest.java b/src/test/java/com/amazonaws/services/kinesis/clientlibrary/lib/worker/WorkerTest.java
index ce406dce..ae3b883a 100644
--- a/src/test/java/com/amazonaws/services/kinesis/clientlibrary/lib/worker/WorkerTest.java
+++ b/src/test/java/com/amazonaws/services/kinesis/clientlibrary/lib/worker/WorkerTest.java
@@ -19,6 +19,8 @@ import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.CoreMatchers.isA;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.greaterThanOrEqualTo;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.mockito.Matchers.any;
 import static org.mockito.Matchers.anyInt;
@@ -41,6 +43,7 @@ import java.io.File;
 import java.lang.Thread.State;
 import java.lang.reflect.Field;
 import java.math.BigInteger;
+import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
@@ -108,6 +111,13 @@ import com.amazonaws.services.kinesis.model.HashKeyRange;
 import com.amazonaws.services.kinesis.model.Record;
 import com.amazonaws.services.kinesis.model.SequenceNumberRange;
 import com.amazonaws.services.kinesis.model.Shard;
+import com.amazonaws.services.kinesis.clientlibrary.proxies.KinesisProxy;
+import com.amazonaws.services.kinesis.model.DescribeStreamResult;
+import com.amazonaws.services.kinesis.model.ExpiredIteratorException;
+import com.amazonaws.services.kinesis.model.GetRecordsResult;
+import com.amazonaws.services.kinesis.model.InvalidArgumentException;
+import com.amazonaws.services.kinesis.model.PutRecordResult;
+import com.amazonaws.services.kinesis.model.ResourceNotFoundException;
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
 
@@ -1474,6 +1484,71 @@ public class WorkerTest {
 
     }
 
+    @Test
+    public void testBuilderWithDefaultKinesisProxy() {
+        IRecordProcessorFactory recordProcessorFactory = mock(IRecordProcessorFactory.class);
+
+        Worker.Builder builder = new Worker.Builder()
+            .recordProcessorFactory(recordProcessorFactory)
+            .config(config);
+        builder.build();
+        assertNotNull(builder.getKinesisProxy());
+        assertTrue(builder.getKinesisProxy() instanceof KinesisProxy);
+    }
+
+    @Test
+    public void testBuilderWhenKinesisProxyIsSet() {
+        IRecordProcessorFactory recordProcessorFactory = mock(IRecordProcessorFactory.class);
+        IKinesisProxy kinesisProxy = new DummyKinesisProxy();
+        Worker.Builder builder = new Worker.Builder()
+            .recordProcessorFactory(recordProcessorFactory)
+            .kinesisProxy(kinesisProxy)
+            .config(config);
+        builder.build();
+        assertNotNull(builder.getKinesisProxy());
+        assertTrue(builder.getKinesisProxy() instanceof DummyKinesisProxy);
+    }
+
+    // KinesisProxyImplementation to test KinesisProxy injection.
+    private class DummyKinesisProxy implements IKinesisProxy {
+        @Override public GetRecordsResult get(String shardIterator, int maxRecords)
+            throws ResourceNotFoundException, InvalidArgumentException, ExpiredIteratorException {
+            return null;
+        }
+
+        @Override public DescribeStreamResult getStreamInfo(String startShardId) throws ResourceNotFoundException {
+            return null;
+        }
+
+        @Override public Set<String> getAllShardIds() throws ResourceNotFoundException {
+            return null;
+        }
+
+        @Override public List<Shard> getShardList() throws ResourceNotFoundException {
+            return null;
+        }
+
+        @Override public String getIterator(String shardId, String iteratorEnum, String sequenceNumber)
+            throws ResourceNotFoundException, InvalidArgumentException {
+            return null;
+        }
+
+        @Override public String getIterator(String shardId, String iteratorEnum)
+            throws ResourceNotFoundException, InvalidArgumentException {
+            return null;
+        }
+
+        @Override public String getIterator(String shardId, Date timestamp)
+            throws ResourceNotFoundException, InvalidArgumentException {
+            return null;
+        }
+
+        @Override public PutRecordResult put(String sequenceNumberForOrdering, String explicitHashKey,
+            String partitionKey, ByteBuffer data) throws ResourceNotFoundException, InvalidArgumentException {
+            return null;
+        }
+    }
+
     private abstract class InjectableWorker extends Worker {
         InjectableWorker(String applicationName, IRecordProcessorFactory recordProcessorFactory,
                 KinesisClientLibConfiguration config, StreamConfig streamConfig,