diff --git a/pkgs/development/ocaml-modules/bjack/default.nix b/pkgs/development/ocaml-modules/bjack/default.nix
index a102d27c287..197d31638d6 100644
--- a/pkgs/development/ocaml-modules/bjack/default.nix
+++ b/pkgs/development/ocaml-modules/bjack/default.nix
@@ -4,13 +4,11 @@ buildDunePackage rec {
   pname = "bjack";
   version = "0.1.6";
 
-  useDune2 = true;
-
   src = fetchFromGitHub {
     owner = "savonet";
     repo = "ocaml-bjack";
     rev = "v${version}";
-    sha256 = "1gf31a8i9byp6npn0x6gydcickn6sf5dnzmqr2c1b9jn2nl7334c";
+    hash = "sha256-jIxxqBVWphWYyLh+24rTxk4WWfPPdGCvNdevFJEKw70=";
   };
 
   buildInputs = [ dune-configurator ] ++ lib.optionals stdenv.isDarwin [ Accelerate CoreAudio ];