diff --git a/test/Model/TypesSpec.hs b/test/Model/TypesSpec.hs
index b1c3d8a8b..e45b6ff49 100644
--- a/test/Model/TypesSpec.hs
+++ b/test/Model/TypesSpec.hs
@@ -391,6 +391,9 @@ instance Arbitrary SchoolAuthorshipStatementMode where
 instance Arbitrary SheetAuthorshipStatementMode where
   arbitrary = genericArbitrary
 
+instance Arbitrary WorkflowWorkflowListType where
+  arbitrary = genericArbitrary
+
 
 spec :: Spec
 spec = do