diff --git a/pkgs/development/ocaml-modules/extlib/1.7.7.nix b/pkgs/development/ocaml-modules/extlib/1.7.7.nix
index d27fe085569..7ab61a146a9 100644
--- a/pkgs/development/ocaml-modules/extlib/1.7.7.nix
+++ b/pkgs/development/ocaml-modules/extlib/1.7.7.nix
@@ -1,14 +1,33 @@
 # Older version of extlib for Haxe 4.0 and 4.1.
 # May be replaceable by the next extlib + extlib-base64 release.
-{ lib, fetchurl, ocaml, ocaml_extlib }:
+{ stdenv, lib, fetchurl, ocaml, findlib, cppo
+# De facto, option minimal seems to be the default. See the README.
+, minimal ? true
+}:
 
-ocaml_extlib.overrideAttrs (x: rec {
+stdenv.mkDerivation rec {
+  pname = "ocaml${ocaml.version}-extlib";
   version = "1.7.7";
+
   src = fetchurl {
-    url = "https://github.com/ygrek/ocaml-extlib/releases/download/${version}/extlib-${version}.tar.gz";
+    url = "https://ygrek.org/p/release/ocaml-extlib/extlib-${version}.tar.gz";
     sha256 = "1sxmzc1mx3kg62j8kbk0dxkx8mkf1rn70h542cjzrziflznap0s1";
   };
-  meta = x.meta // {
+
+  nativeBuildInputs = [ ocaml findlib cppo ];
+
+  strictDeps = true;
+
+  createFindlibDestdir = true;
+
+  makeFlags = lib.optional minimal "minimal=1";
+
+  meta = {
+    homepage = "https://github.com/ygrek/ocaml-extlib";
+    description = "Enhancements to the OCaml Standard Library modules";
+    license = lib.licenses.lgpl21Only;
+    inherit (ocaml.meta) platforms;
+    maintainers = [ lib.maintainers.sternenseemann ];
     broken = lib.versionAtLeast ocaml.version "4.12";
   };
-})
+}
diff --git a/pkgs/development/ocaml-modules/extlib/default.nix b/pkgs/development/ocaml-modules/extlib/default.nix
index 7baee7a6032..35b8c59091c 100644
--- a/pkgs/development/ocaml-modules/extlib/default.nix
+++ b/pkgs/development/ocaml-modules/extlib/default.nix
@@ -1,30 +1,24 @@
-{ stdenv, lib, fetchurl, ocaml, findlib, cppo
-# De facto, option minimal seems to be the default. See the README.
-, minimal ? true
-}:
+{ buildDunePackage, lib, fetchurl, cppo }:
 
-stdenv.mkDerivation rec {
-  pname = "ocaml${ocaml.version}-extlib";
-  version = "1.7.8";
+buildDunePackage rec {
+  pname = "extlib";
+  version = "1.7.9";
+
+  minimalOCamlVersion = "4.02";
 
   src = fetchurl {
-    url = "https://ygrek.org/p/release/ocaml-extlib/extlib-${version}.tar.gz";
-    sha256 = "0npq4hq3zym8nmlyji7l5cqk6drx2rkcx73d60rxqh5g8dla8p4k";
+    url = "https://ygrek.org/p/release/ocaml-${pname}/${pname}-${version}.tar.gz";
+    sha512 = "2386ac69f037ea520835c0624d39ae9fbffe43a20b18e247de032232ed6f419d667b53d2314c6f56dc71d368bf0b6201a56c2f3f2a5bdfd933766c5a6cb98768";
   };
 
-  nativeBuildInputs = [ ocaml findlib cppo ];
+  nativeBuildInputs = [ cppo ];
 
-  strictDeps = true;
-
-  createFindlibDestdir = true;
-
-  makeFlags = lib.optional minimal "minimal=1";
+  doCheck = true;
 
   meta = {
     homepage = "https://github.com/ygrek/ocaml-extlib";
     description = "Enhancements to the OCaml Standard Library modules";
     license = lib.licenses.lgpl21Only;
-    inherit (ocaml.meta) platforms;
     maintainers = [ lib.maintainers.sternenseemann ];
   };
 }
diff --git a/pkgs/top-level/ocaml-packages.nix b/pkgs/top-level/ocaml-packages.nix
index 0a218ef11d9..85464170df3 100644
--- a/pkgs/top-level/ocaml-packages.nix
+++ b/pkgs/top-level/ocaml-packages.nix
@@ -1260,9 +1260,9 @@ let
 
     ocaml-protoc = callPackage ../development/ocaml-modules/ocaml-protoc { };
 
-    ocaml_extlib = ocaml_extlib-1-7-8;
+    ocaml_extlib = ocaml_extlib-1-7-9;
 
-    ocaml_extlib-1-7-8 = callPackage ../development/ocaml-modules/extlib { };
+    ocaml_extlib-1-7-9 = callPackage ../development/ocaml-modules/extlib { };
 
     ocaml_extlib-1-7-7 = callPackage ../development/ocaml-modules/extlib/1.7.7.nix { };
 
@@ -1621,10 +1621,7 @@ let
 
     omake_rc1 = callPackage ../development/tools/ocaml/omake/0.9.8.6-rc1.nix { };
 
-    google-drive-ocamlfuse = callPackage ../applications/networking/google-drive-ocamlfuse {
-      # needs Base64 module
-      ocaml_extlib = ocaml_extlib.override { minimal = false; };
-    };
+    google-drive-ocamlfuse = callPackage ../applications/networking/google-drive-ocamlfuse { };
 
     hol_light = callPackage ../applications/science/logic/hol_light { };