diff --git a/lib/pkgs/bmxd.nix b/lib/pkgs/bmxd.nix
index 5b7b7391..bf287e99 100644
--- a/lib/pkgs/bmxd.nix
+++ b/lib/pkgs/bmxd.nix
@@ -4,16 +4,22 @@
 
 with pkgs;
 let
-  path = "${src}/feeds/19.07/feeds-own/bmxd";
-  makefile = builtins.readFile "${path}/Makefile";
+  path = "feeds/19.07/feeds-own/bmxd";
+  makefile = builtins.readFile "${src}/${path}/Makefile";
   makeDef = name:
     builtins.elemAt (builtins.match ".*?${name}:=([^\n]+).*?" makefile) 0;
   name = makeDef "PKG_NAME";
   version = makeDef "PKG_VERSION";
   release = makeDef "PKG_RELEASE";
+  patch = fetchurl {
+    url = "https://gitlab.freifunk-dresden.de/firmware-developer/firmware/merge_requests/36.patch";
+    sha256 = "10gm1fqg2s8c261i0j1py3sfyyzr0h5b6wwdsgg3icn7lfjd6k75";
+  };
 in stdenv.mkDerivation {
   name = "${name}-${version}-${release}";
-  src = "${path}/sources";
+  inherit src;
+  patches = [ patch ];
+  buildPhase = "cd ${path}/sources";
   installPhase = ''
     make install SBINDIR=$out/sbin
   '';