diff --git a/src/main/java/com/redhat/red/build/koji/model/json/BuildComponent.java b/src/main/java/com/redhat/red/build/koji/model/json/BuildComponent.java
index 632b75b..4616fa5 100644
--- a/src/main/java/com/redhat/red/build/koji/model/json/BuildComponent.java
+++ b/src/main/java/com/redhat/red/build/koji/model/json/BuildComponent.java
@@ -33,7 +33,7 @@
  *
  * @author Honza Brázdil <jbrazdil@redhat.com>
  */
-@JsonTypeInfo( use = Id.NAME, include = As.PROPERTY, property = TYPE )
+@JsonTypeInfo( use = Id.NAME, include = As.EXISTING_PROPERTY, property = TYPE, visible = true )
 @JsonSubTypes( {
 @JsonSubTypes.Type( value = FileBuildComponent.class, name = "file" ),
 @JsonSubTypes.Type( value = RPMBuildComponent.class, name = "rpm" )
diff --git a/src/test/java/com/redhat/red/build/koji/model/json/BuildComponentTest.java b/src/test/java/com/redhat/red/build/koji/model/json/BuildComponentTest.java
index 01464fa..561c2b9 100644
--- a/src/test/java/com/redhat/red/build/koji/model/json/BuildComponentTest.java
+++ b/src/test/java/com/redhat/red/build/koji/model/json/BuildComponentTest.java
@@ -15,6 +15,7 @@
  */
 package com.redhat.red.build.koji.model.json;
 
+import com.fasterxml.jackson.core.JsonParser;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -32,16 +33,18 @@ public class BuildComponentTest
     public void jsonRoundTripFile() throws VerificationException, IOException
     {
         FileBuildComponent src = new FileBuildComponent.Builder( "foo.txt" )
-                .withFileSize(42)
+                .withFileSize( 42 )
                 .withChecksum( "md5", "2a4b3cd54e6f" )
                 .build();
 
-        String json = mapper.writeValueAsString(src);
-        System.out.println(json);
+        String json = mapper.writeValueAsString( src );
+        System.out.println( json );
+
+        mapper.reader().with( JsonParser.Feature.STRICT_DUPLICATE_DETECTION ).readTree( json );
 
         BuildComponent out = mapper.readValue( json, BuildComponent.class );
 
-        assertThat(out, equalTo(src));
+        assertThat( out, equalTo( src ) );
     }
 
     @Test
@@ -57,6 +60,8 @@ public void jsonRoundTripRPM() throws VerificationException, IOException
         String json = mapper.writeValueAsString( src );
         System.out.println( json );
 
+        mapper.reader().with( JsonParser.Feature.STRICT_DUPLICATE_DETECTION ).readTree( json );
+
         BuildComponent out = mapper.readValue( json, BuildComponent.class );
 
         assertThat( out, equalTo( src ) );