diff --git a/pkgs/development/ocaml-modules/pgocaml/default.nix b/pkgs/development/ocaml-modules/pgocaml/default.nix
index bd9f7a09a8d8..ea8a52ae2348 100644
--- a/pkgs/development/ocaml-modules/pgocaml/default.nix
+++ b/pkgs/development/ocaml-modules/pgocaml/default.nix
@@ -13,13 +13,13 @@
   sexplib,
 }:
 
-buildDunePackage rec {
+buildDunePackage (finalAttrs: {
   pname = "pgocaml";
   version = "4.4.0";
   src = fetchFromGitHub {
     owner = "darioteixeira";
     repo = "pgocaml";
-    rev = "v${version}";
+    rev = "v${finalAttrs.version}";
     hash = "sha256-Mz3zVgXas1UivH/BVARx5kWClgr9v9YcGarwaD961tU=";
   };
 
@@ -43,4 +43,4 @@ buildDunePackage rec {
     license = lib.licenses.lgpl2Only;
     maintainers = with lib.maintainers; [ vbgl ];
   };
-}
+})