diff --git a/pkgs/applications/networking/p2p/mldonkey/default.nix b/pkgs/applications/networking/p2p/mldonkey/default.nix
index 1291caa088ff..7bc5e2f59679 100644
--- a/pkgs/applications/networking/p2p/mldonkey/default.nix
+++ b/pkgs/applications/networking/p2p/mldonkey/default.nix
@@ -20,6 +20,11 @@ stdenv.mkDerivation rec {
       url = "https://github.com/ygrek/mldonkey/commit/a153f0f7a4826d86d51d4bacedc0330b70fcbc34.patch";
       hash = "sha256-/Muk3mPFjQJ48FqaozGa7o8YSPhDLXRz9K1EyfxlzC8=";
     })
+    # Fixes OCaml 4.14 compat
+    (fetchpatch {
+      url = "https://github.com/FabioLolix/AUR-artifacts/raw/6721c2d4ef0be9a99499ecf2787e378e50b915e9/mldonkey-fix-build.patch";
+      hash = "sha256-HPW/CKfhywy+Km5/64Iok4tO9LJjAk53jVlsYzIRPfs=";
+    })
   ];
 
   preConfigure = ''
@@ -28,7 +33,7 @@ stdenv.mkDerivation rec {
   '';
 
   strictDeps = true;
-  nativeBuildInputs = with ocamlPackages; [ ocaml camlp4];
+  nativeBuildInputs = with ocamlPackages; [ ocaml camlp4 ];
   buildInputs = (with ocamlPackages; [ num ]) ++ [ zlib ];
 
   meta = {
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 3f2ef63b7bb6..5d7fa20a7195 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -31564,7 +31564,7 @@ with pkgs;
   mjpg-streamer = callPackage ../applications/video/mjpg-streamer { };
 
   mldonkey = callPackage ../applications/networking/p2p/mldonkey {
-    ocamlPackages = ocaml-ng.mkOcamlPackages (ocaml-ng.ocamlPackages_4_13.ocaml.override {
+    ocamlPackages = ocaml-ng.mkOcamlPackages (ocaml-ng.ocamlPackages_4_14.ocaml.override {
       unsafeStringSupport = true;
     });
   };