diff --git a/pkgs/development/ocaml-modules/bigarray-compat/default.nix b/pkgs/development/ocaml-modules/bigarray-compat/default.nix
index 83c35edcc41d..fd690cfdd5b3 100644
--- a/pkgs/development/ocaml-modules/bigarray-compat/default.nix
+++ b/pkgs/development/ocaml-modules/bigarray-compat/default.nix
@@ -6,7 +6,7 @@ buildDunePackage rec {
 
   useDune2 = true;
 
-  minimalOCamlVersion = "4.03";
+  minimalOCamlVersion = "4.02";
 
   src = fetchFromGitHub {
     owner = "mirage";
diff --git a/pkgs/development/tools/ocaml/dune/2.nix b/pkgs/development/tools/ocaml/dune/2.nix
index c55aae7878ef..30962eeba311 100644
--- a/pkgs/development/tools/ocaml/dune/2.nix
+++ b/pkgs/development/tools/ocaml/dune/2.nix
@@ -6,11 +6,11 @@ else
 
 stdenv.mkDerivation rec {
   pname = "dune";
-  version = "2.9.2";
+  version = "2.9.3";
 
   src = fetchurl {
     url = "https://github.com/ocaml/dune/releases/download/${version}/dune-site-${version}.tbz";
-    sha256 = "sha256-uOfMUH+5eLRfb9yDnysyAdLB5hHkqOlyyMjP2FIudEc=";
+    sha256 = "sha256:1ml8bxym8sdfz25bx947al7cvsi2zg5lcv7x9w6xb01cmdryqr9y";
   };
 
   nativeBuildInputs = [ ocaml findlib ];
diff --git a/pkgs/development/tools/ocaml/js_of_ocaml/ocamlbuild.nix b/pkgs/development/tools/ocaml/js_of_ocaml/ocamlbuild.nix
index 3375e5ac5a0f..c67d05c15038 100644
--- a/pkgs/development/tools/ocaml/js_of_ocaml/ocamlbuild.nix
+++ b/pkgs/development/tools/ocaml/js_of_ocaml/ocamlbuild.nix
@@ -7,7 +7,7 @@ buildDunePackage {
 
   inherit (js_of_ocaml-compiler) version src meta useDune2;
 
-  minimalOCamlVersion = "4.03";
+  minimalOCamlVersion = "4.02";
 
   propagatedBuildInputs = [ ocamlbuild ];
 }