diff --git a/codegen/src/main/scala/overflowdb/codegen/CodeGen.scala b/codegen/src/main/scala/overflowdb/codegen/CodeGen.scala
index 2c65d0e5..223eb93b 100644
--- a/codegen/src/main/scala/overflowdb/codegen/CodeGen.scala
+++ b/codegen/src/main/scala/overflowdb/codegen/CodeGen.scala
@@ -152,6 +152,7 @@ class CodeGen(schema: Schema) {
          |      case other => other
          |    }
          |
+         |  def newDiffGraphBuilder: DiffGraphBuilder = new DiffGraphBuilder
          |}
          |
          |