diff --git a/conf/defaults.config b/conf/defaults.config
index 8abf21ba86..b2755cf22f 100644
--- a/conf/defaults.config
+++ b/conf/defaults.config
@@ -1218,7 +1218,7 @@ ${pg}{modules} = [
 	[qw(Locale::Maketext)],
 	[qw(WeBWorK::PG::Localize)],
 	[qw(Mojo::JSON)],
-	[qw(Rserve Class::Tiny IO::Handle)],
+	[qw(Rserve IO::Handle)],
 	[qw(DragNDrop)],
 	[qw(Types::Serialiser)],
 	[qw(strict)],