diff --git a/packages/ezjs_crypto/ezjs_crypto.0.1/opam b/packages/ezjs_crypto/ezjs_crypto.0.1/opam
index 961e797af9d4..a228521c2104 100644
--- a/packages/ezjs_crypto/ezjs_crypto.0.1/opam
+++ b/packages/ezjs_crypto/ezjs_crypto.0.1/opam
@@ -10,6 +10,7 @@ depends: [
   "ocaml" {>= "4.05"}
   "dune" {>= "2.0"}
   "ezjs_min" {>= "0.2"}
+  "js_of_ocaml-compiler" {>= "3.3.0" & < "5.9.0"}
 ]
 build: [
   ["dune" "subst"] {dev}
@@ -32,4 +33,4 @@ url {
     "md5=aff005185a07842dc89989faf7dba12c"
     "sha512=9d85adbe0a0f519dc333c19fe2ffe558938ed3bfbd33e2d05e80b85b12823ab197a734bac5542432753116f0c23f0f553b7b4719662aad587b0d38977231c97a"
   ]
-}
\ No newline at end of file
+}
diff --git a/packages/js_of_ocaml/js_of_ocaml.3.3.0/opam b/packages/js_of_ocaml/js_of_ocaml.3.3.0/opam
index 649b36fc85b9..952061b16ada 100644
--- a/packages/js_of_ocaml/js_of_ocaml.3.3.0/opam
+++ b/packages/js_of_ocaml/js_of_ocaml.3.3.0/opam
@@ -17,7 +17,7 @@ depends: [
   "js_of_ocaml-compiler" {= version}
 ]
 conflicts: [
-  "ppx_tools_versioned"     {<= "5.0beta0"}
+  "ppx_tools_versioned"     {< "5.0"}
 ]
 
 synopsis: "Compiler from OCaml bytecode to Javascript"