diff --git a/pkgs/applications/networking/p2p/opentracker/default.nix b/pkgs/applications/networking/p2p/opentracker/default.nix
index 82480b1ed21..8beb2f7d377 100644
--- a/pkgs/applications/networking/p2p/opentracker/default.nix
+++ b/pkgs/applications/networking/p2p/opentracker/default.nix
@@ -11,6 +11,11 @@ stdenv.mkDerivation {
 
   buildInputs = [ libowfat zlib ];
 
+  makeFlags = [
+    "LIBOWFAT_HEADERS=${libowfat}/include/libowfat"
+    "LIBOWFAT_LIBRARY=${libowfat}/lib"
+  ];
+
   installPhase = ''
     runHook preInstall
     install -D opentracker $out/bin/opentracker
diff --git a/pkgs/development/libraries/libowfat/default.nix b/pkgs/development/libraries/libowfat/default.nix
index 5f434a7ae75..06871158609 100644
--- a/pkgs/development/libraries/libowfat/default.nix
+++ b/pkgs/development/libraries/libowfat/default.nix
@@ -8,17 +8,6 @@ stdenv.mkDerivation rec {
     sha256 = "1hcqg7pvy093bxx8wk7i4gvbmgnxz2grxpyy7b4mphidjbcv7fgl";
   };
 
-  # Dirty patch because 0.32 "moved headers to <libowfat/> upon install"
-  # but it breaks gatling-0.15 and opentracker-2018-05-26 ...
-  postPatch = ''
-    substituteInPlace GNUmakefile --replace \
-      'install -d $(DESTDIR)$(INCLUDEDIR)/libowfat' \
-      'install -d $(DESTDIR)$(INCLUDEDIR)'
-    substituteInPlace GNUmakefile --replace \
-      'install -m 644 $(INCLUDES) $(DESTDIR)$(INCLUDEDIR)/libowfat' \
-      'install -m 644 $(INCLUDES) $(DESTDIR)$(INCLUDEDIR)'
-  '';
-
   makeFlags = [ "prefix=$(out)" ];
   enableParallelBuilding = true;
 
diff --git a/pkgs/servers/http/gatling/default.nix b/pkgs/servers/http/gatling/default.nix
index 9157c09cbeb..0c095c55e97 100644
--- a/pkgs/servers/http/gatling/default.nix
+++ b/pkgs/servers/http/gatling/default.nix
@@ -1,7 +1,7 @@
-{ stdenv, fetchurl, libowfat, zlib, openssl }:
+{ stdenv, fetchurl, libowfat, libcap, zlib, openssl }:
 
 let
-  version = "0.15";
+  version = "0.16";
 in
 stdenv.mkDerivation rec {
   pname = "gatling";
@@ -9,10 +9,10 @@ stdenv.mkDerivation rec {
 
   src = fetchurl {
     url = "https://www.fefe.de/gatling/${pname}-${version}.tar.xz";
-    sha256 = "194srqyja3pczpbl6l169zlvx179v7ln0m6yipmhvj6hrv82k8vg";
+    sha256 = "0nrnws5qrl4frqcsfa9z973vv5mifgr9z170qbvg3mq1wa7475jz";
   };
 
-  buildInputs = [  libowfat zlib openssl.dev ];
+  buildInputs = [ libowfat libcap zlib openssl.dev ];
 
   configurePhase = ''
     substituteInPlace Makefile --replace "/usr/local" "$out"