diff --git a/pkgs/development/ocaml-modules/janestreet/ppx_type_conv-113_33_02.nix b/pkgs/development/ocaml-modules/janestreet/ppx_type_conv-113_33_02.nix
new file mode 100644
index 00000000000..49cfc19321d
--- /dev/null
+++ b/pkgs/development/ocaml-modules/janestreet/ppx_type_conv-113_33_02.nix
@@ -0,0 +1,21 @@
+{ stdenv, fetchurl, ocaml, findlib, ocamlbuild, opam, topkg
+, ppx_core, ppx_deriving, ppx_driver
+}:
+
+stdenv.mkDerivation {
+  name = "ocaml${ocaml.version}-ppx_type_conv-133.33.02+4.03";
+  src = fetchurl {
+    url = http://ocaml.janestreet.com/ocaml-core/113.33/files/ppx_type_conv-113.33.02+4.03.tar.gz;
+    sha256 = "0y7hsh152gcj89i6cr3b9kxgdnb2sx8vhaq2bdvbcc9zrirwq4d2";
+  };
+
+  buildInputs = [ ocaml findlib ocamlbuild opam ppx_deriving ];
+  propagatedBuildInputs = [ ppx_core ppx_driver ];
+
+  inherit (topkg) installPhase;
+
+  meta = {
+    license = stdenv.lib.licenses.asl20;
+    inherit (ocaml.meta) platforms;
+  };
+}
diff --git a/pkgs/top-level/ocaml-packages.nix b/pkgs/top-level/ocaml-packages.nix
index 218cb12e69e..09443b93db0 100644
--- a/pkgs/top-level/ocaml-packages.nix
+++ b/pkgs/top-level/ocaml-packages.nix
@@ -567,7 +567,10 @@ let
 
     ppx_driver = callPackage ../development/ocaml-modules/janestreet/ppx-driver.nix {};
 
-    ppx_type_conv = callPackage ../development/ocaml-modules/janestreet/ppx-type-conv.nix {};
+    ppx_type_conv =
+      if lib.versionOlder "4.03" ocaml.version
+      then callPackage ../development/ocaml-modules/janestreet/ppx_type_conv-113_33_02.nix { }
+      else callPackage ../development/ocaml-modules/janestreet/ppx-type-conv.nix {};
 
     ppx_compare = callPackage ../development/ocaml-modules/janestreet/ppx-compare.nix {};