diff --git a/packages/ojs-base/ojs-base.0.6.0/opam b/packages/ojs-base/ojs-base.0.6.0/opam
index 065902f79683..8f052a6b7d21 100644
--- a/packages/ojs-base/ojs-base.0.6.0/opam
+++ b/packages/ojs-base/ojs-base.0.6.0/opam
@@ -11,7 +11,7 @@ bug-reports: "https://framagit.org/zoggy/ojs-base/-/issues"
 depends: [
   "ocaml" {>= "4.12.0"}
   "ocamlfind" {build}
-  "js_of_ocaml" {>= "3.9.0"}
+  "js_of_ocaml" {>= "3.9.0" & < "6.0.0" }
   "websocket" {>= "2.14"}
   "websocket-lwt-unix" {>= "2.14"}
   "lwt" {>= "5.4.0" & < "5.8.0"}