diff --git a/pkgs/development/tools/ocaml/js_of_ocaml/default.nix b/pkgs/development/tools/ocaml/js_of_ocaml/default.nix
index 10f00c4e542..4443d2d5340 100644
--- a/pkgs/development/tools/ocaml/js_of_ocaml/default.nix
+++ b/pkgs/development/tools/ocaml/js_of_ocaml/default.nix
@@ -2,7 +2,7 @@
  cmdliner}:
 
 stdenv.mkDerivation {
-  name = "js_of_ocaml";
+  name = "js_of_ocaml-2.5";
   src = fetchurl {
     url = https://github.com/ocsigen/js_of_ocaml/archive/2.5.tar.gz;
     sha256 = "1prm08nf8szmd3p13ysb0yx1cy6lr671bnwsp25iny8hfbs39sjv";