diff --git a/nix/packages/by-name/necrolib/package.nix b/nix/packages/by-name/necrolib/package.nix
index 9b8ac1c2..50ea1abb 100644
--- a/nix/packages/by-name/necrolib/package.nix
+++ b/nix/packages/by-name/necrolib/package.nix
@@ -1,14 +1,10 @@
 {
   fetchFromGitLab,
-  ocaml-ng,
-  ocamlPackages ? ocaml-ng.ocamlPackages_5_1,
+  ocamlPackages,
 }:
-let
-  version = "v0.16.2";
-in
-ocamlPackages.buildDunePackage {
+ocamlPackages.buildDunePackage (finalAttrs: {
   pname = "necrolib";
-  inherit version;
+  version = "0.16.2";
 
   minimalOCamlVersion = "5.1.1";
 
@@ -16,8 +12,8 @@ ocamlPackages.buildDunePackage {
     domain = "gitlab.inria.fr";
     owner = "skeletons";
     repo = "necro";
-    rev = version;
-    hash = "sha256-KoSKJD5jy+GY5QKKMUTW5gc0V/5l/klHrJMdC8aPnj8=";
+    rev = "v${finalAttrs.version}";
+    hash = "sha256-u5evoyVW6RP7uwvdH7MK0cEbXt+GEAMw78MiOLlYTA0=";
   };
 
   duneVersion = "3";
@@ -26,4 +22,4 @@ ocamlPackages.buildDunePackage {
     ocamlPackages.ocamlgraph
     ocamlPackages.dune-build-info
   ];
-}
+})