diff --git a/pkgs/development/ocaml-modules/pecu/default.nix b/pkgs/development/ocaml-modules/pecu/default.nix
index 22c1913635f..746c75fccc1 100644
--- a/pkgs/development/ocaml-modules/pecu/default.nix
+++ b/pkgs/development/ocaml-modules/pecu/default.nix
@@ -4,9 +4,9 @@ buildDunePackage rec {
   pname = "pecu";
   version = "0.6";
 
-  useDune2 = true;
+  duneVersion = "3";
 
-  minimumOCamlVersion = "4.03";
+  minimalOCamlVersion = "4.03";
 
   src = fetchurl {
     url = "https://github.com/mirage/pecu/releases/download/v${version}/pecu-v${version}.tbz";