diff --git a/test/model/semantics/dune b/test/model/semantics/dune
index 3eb91bec40..9e2dcacdda 100644
--- a/test/model/semantics/dune
+++ b/test/model/semantics/dune
@@ -1,6 +1,7 @@
 (library
  (name odoc_model_semantics_test)
  (package odoc)
+ (optional)
  (inline_tests)
  (enabled_if
   (>= %{ocaml_version} 4.04.1))
diff --git a/test/odoc_print/dune b/test/odoc_print/dune
index be81e1d897..4c69f6f37d 100644
--- a/test/odoc_print/dune
+++ b/test/odoc_print/dune
@@ -1,6 +1,7 @@
 (library
  (name type_desc_to_yojson)
  (package odoc)
+ (optional)
  (modules type_desc_to_yojson)
  (libraries odoc_model_desc yojson))