diff --git a/pkgs/development/ocaml-modules/janestreet/sexplib-113_33_00.nix b/pkgs/development/ocaml-modules/janestreet/sexplib-113_33_00.nix
new file mode 100644
index 00000000000..93808a56562
--- /dev/null
+++ b/pkgs/development/ocaml-modules/janestreet/sexplib-113_33_00.nix
@@ -0,0 +1,18 @@
+{ stdenv, fetchurl, ocaml, findlib, ocamlbuild, opam, topkg }:
+
+stdenv.mkDerivation {
+  name = "ocaml${ocaml.version}-sexplib-133.33.00+4.03";
+  src = fetchurl {
+    url = http://ocaml.janestreet.com/ocaml-core/113.33/files/sexplib-113.33.00+4.03.tar.gz;
+    sha256 = "1dirdrags3z8m80z1vczfnpdfzgcvm2wyy7g61fxdr8h3jgixpl3";
+  };
+
+  buildInputs = [ ocaml findlib ocamlbuild opam ];
+
+  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 339f6eb84e3..ebc09ecc84f 100644
--- a/pkgs/top-level/ocaml-packages.nix
+++ b/pkgs/top-level/ocaml-packages.nix
@@ -613,7 +613,9 @@ let
       else fieldslib_p4;
 
     sexplib =
-      if lib.versionOlder "4.02" ocaml.version
+      if lib.versionOlder "4.03" ocaml.version
+      then callPackage ../development/ocaml-modules/janestreet/sexplib-113_33_00.nix {}
+      else if lib.versionOlder "4.02" ocaml.version
       then callPackage ../development/ocaml-modules/janestreet/sexplib.nix {}
       else sexplib_p4;