diff --git a/src_test/ppx_deriving/test_intf.ml b/src_test/ppx_deriving/test_intf.ml
index af05751..e5d84e2 100644
--- a/src_test/ppx_deriving/test_intf.ml
+++ b/src_test/ppx_deriving/test_intf.ml
@@ -1 +1,5 @@
 [%%import: type a = Stuff.a]
+
+module type Example = sig
+  module type InnerModule = [%import: (module Stuff.S_optional)]
+end
diff --git a/src_test/ppx_deriving/test_intf.mli b/src_test/ppx_deriving/test_intf.mli
index af05751..e5d84e2 100644
--- a/src_test/ppx_deriving/test_intf.mli
+++ b/src_test/ppx_deriving/test_intf.mli
@@ -1 +1,5 @@
 [%%import: type a = Stuff.a]
+
+module type Example = sig
+  module type InnerModule = [%import: (module Stuff.S_optional)]
+end