diff --git a/tiny_httpd.opam b/tiny_httpd.opam
index f76c5e23..967f15c8 100644
--- a/tiny_httpd.opam
+++ b/tiny_httpd.opam
@@ -14,7 +14,7 @@ depends: [
   "base-threads"
   "ocaml" { >= "4.03.0" }
   "odoc" {with-doc}
-  "qtest" {with-test}
+  "qtest" { >= "2.9" & with-test}
   "qcheck" {with-test}
 ]
 tags: [ "http" "thread" "server" "tiny_httpd" "http_of_dir" "simplehttpserver" ]