diff --git a/pkgs/development/ocaml-modules/charInfo_width/default.nix b/pkgs/development/ocaml-modules/charInfo_width/default.nix
index 5b9814cea69..aaf18110454 100644
--- a/pkgs/development/ocaml-modules/charInfo_width/default.nix
+++ b/pkgs/development/ocaml-modules/charInfo_width/default.nix
@@ -3,7 +3,7 @@
 buildDunePackage rec {
   pname = "charInfo_width";
   version = "1.1.0";
-  useDune2 = true;
+  duneVersion = "3";
   src = fetchzip {
     url = "https://bitbucket.org/zandoye/charinfo_width/get/${version}.tar.bz2";
     sha256 = "19mnq9a1yr16srqs8n6hddahr4f9d2gbpmld62pvlw1ps7nfrp9w";