ocamlPackages.base64: 2.0.0 -> 3.2.0

Keep the legacy version under attribute `base64_2`

pkgs/development/ocaml-modules/base64/default.nix

@@ -1,24 +1,26 @@
-{ stdenv, fetchzip, ocaml, findlib, ocamlbuild }:
+{ lib, fetchzip, buildDunePackage, alcotest, bos }:
 
-let version = "2.0.0"; in
+let version = "3.2.0"; in
 
-stdenv.mkDerivation {
-  name = "ocaml-base64-${version}";
+buildDunePackage {
+  pname = "base64";
+  inherit version;
 
   src = fetchzip {
     url = "https://github.com/mirage/ocaml-base64/archive/v${version}.tar.gz";
-    sha256 = "1nv55gwq5vaxmrcz9ja2s165b1p9fhcxszc1l76043gpa56qm4fs";
+    sha256 = "1ilw3zj0w6cq7i4pvr8m2kv5l5f2y9aldmv72drlwwns013b1gwy";
   };
 
-  buildInputs = [ ocaml findlib ocamlbuild ];
+  minimumOCamlVersion = "4.03";
 
-  createFindlibDestdir = true;
+  buildInputs = [ alcotest bos ];
+
+  doCheck = true;
 
   meta = {
     homepage = https://github.com/mirage/ocaml-base64;
-    platforms = ocaml.meta.platforms or [];
     description = "Base64 encoding and decoding in OCaml";
-    license = stdenv.lib.licenses.isc;
-    maintainers = with stdenv.lib.maintainers; [ vbgl ];
+    license = lib.licenses.isc;
+    maintainers = with lib.maintainers; [ vbgl ];
   };
 }