diff --git a/summingbird-builder/src/main/scala/com/twitter/summingbird/builder/CompletedBuilder.scala b/summingbird-builder/src/main/scala/com/twitter/summingbird/builder/CompletedBuilder.scala
index bbdf17233..5b44169a8 100644
--- a/summingbird-builder/src/main/scala/com/twitter/summingbird/builder/CompletedBuilder.scala
+++ b/summingbird-builder/src/main/scala/com/twitter/summingbird/builder/CompletedBuilder.scala
@@ -36,10 +36,10 @@ import java.io.Serializable
 
 object CompletedBuilder {
   def injectionRegistrar[T: Manifest](injection: Injection[T, Array[Byte]]) =
-    InjectionRegistrar(manifest[T].erasure.asInstanceOf[Class[T]], injection)
+    InjectionRegistrar(manifest[T].runtimeClass.asInstanceOf[Class[T]], injection)
 
   def injectionDefaultRegistrar[T: Manifest](injection: Injection[T, Array[Byte]]) =
-    InjectionDefaultRegistrar(manifest[T].erasure.asInstanceOf[Class[T]], injection)
+    InjectionDefaultRegistrar(manifest[T].runtimeClass.asInstanceOf[Class[T]], injection)
 }
 
 case class CompletedBuilder[P <: Platform[P], K, V](
diff --git a/summingbird-chill/src/main/scala/com/twitter/summingbird/chill/SBChillRegistrar.scala b/summingbird-chill/src/main/scala/com/twitter/summingbird/chill/SBChillRegistrar.scala
index 7fb061833..ce3d01b5c 100644
--- a/summingbird-chill/src/main/scala/com/twitter/summingbird/chill/SBChillRegistrar.scala
+++ b/summingbird-chill/src/main/scala/com/twitter/summingbird/chill/SBChillRegistrar.scala
@@ -31,10 +31,10 @@ import com.twitter.summingbird.batch.{ BatchID, Timestamp }
 object SBChillRegistrar {
 
   def injectionRegistrar[T: Manifest: Codec]: InjectionRegistrar[T] =
-    InjectionRegistrar(manifest[T].erasure.asInstanceOf[Class[T]], implicitly[Codec[T]])
+    InjectionRegistrar(manifest[T].runtimeClass.asInstanceOf[Class[T]], implicitly[Codec[T]])
 
   def injectionDefaultRegistrar[T: Manifest: Codec]: InjectionDefaultRegistrar[T] =
-    InjectionDefaultRegistrar(manifest[T].erasure.asInstanceOf[Class[T]], implicitly[Codec[T]])
+    InjectionDefaultRegistrar(manifest[T].runtimeClass.asInstanceOf[Class[T]], implicitly[Codec[T]])
 
   def kryoRegClass(clazz: Class[_]*) =
     { k: Kryo =>