diff --git a/tests/unit/t_headers.ml b/tests/unit/t_headers.ml
index 7ef6bf3d..4f614483 100644
--- a/tests/unit/t_headers.ml
+++ b/tests/unit/t_headers.ml
@@ -1,4 +1,3 @@
-open Test_util
 open Tiny_httpd_core
 
 (* Test that header size limits are enforced *)