diff --git a/pkgs/development/ocaml-modules/config-file/default.nix b/pkgs/development/ocaml-modules/config-file/default.nix
index f20a7d9b113f..4bb913d544bf 100644
--- a/pkgs/development/ocaml-modules/config-file/default.nix
+++ b/pkgs/development/ocaml-modules/config-file/default.nix
@@ -7,30 +7,34 @@
   camlp4,
 }:
 
-stdenv.mkDerivation rec {
-  pname = "ocaml-config-file";
-  version = "1.2";
+lib.throwIf (lib.versionAtLeast ocaml.version "5.0")
+  "config-file is not available for OCaml ${ocaml.version}"
 
-  src = fetchurl {
-    url = "https://forge.ocamlcore.org/frs/download.php/1387/config-file-${version}.tar.gz";
-    sha256 = "1b02yxcnsjhr05ssh2br2ka4hxsjpdw34ldl3nk33wfnkwk7g67q";
-  };
+  stdenv.mkDerivation
+  rec {
+    pname = "ocaml-config-file";
+    version = "1.2";
 
-  nativeBuildInputs = [
-    ocaml
-    findlib
-    camlp4
-  ];
+    src = fetchurl {
+      url = "https://forge.ocamlcore.org/frs/download.php/1387/config-file-${version}.tar.gz";
+      sha256 = "1b02yxcnsjhr05ssh2br2ka4hxsjpdw34ldl3nk33wfnkwk7g67q";
+    };
 
-  strictDeps = true;
+    nativeBuildInputs = [
+      ocaml
+      findlib
+      camlp4
+    ];
 
-  createFindlibDestdir = true;
+    strictDeps = true;
 
-  meta = {
-    homepage = "http://config-file.forge.ocamlcore.org/";
-    platforms = ocaml.meta.platforms or [ ];
-    description = "OCaml library used to manage the configuration file(s) of an application";
-    license = lib.licenses.lgpl2Plus;
-    maintainers = with lib.maintainers; [ vbgl ];
-  };
-}
+    createFindlibDestdir = true;
+
+    meta = {
+      homepage = "http://config-file.forge.ocamlcore.org/";
+      platforms = ocaml.meta.platforms or [ ];
+      description = "OCaml library used to manage the configuration file(s) of an application";
+      license = lib.licenses.lgpl2Plus;
+      maintainers = with lib.maintainers; [ vbgl ];
+    };
+  }