diff --git a/pkgs/applications/audio/clementine/default.nix b/pkgs/applications/audio/clementine/default.nix
index d916b8957e6..affddd90784 100644
--- a/pkgs/applications/audio/clementine/default.nix
+++ b/pkgs/applications/audio/clementine/default.nix
@@ -54,19 +54,23 @@ let
   ++ stdenv.lib.optionals (withCD) [libcdio]
   ++ stdenv.lib.optionals (withCloud) [sparsehash];
 
+  postPatch = ''
+    sed -i src/CMakeLists.txt \
+      -e 's,-Werror,,g' \
+      -e 's,-Wno-unknown-warning-option,,g' \
+      -e 's,-Wno-unused-private-field,,g'
+    sed -i CMakeLists.txt \
+      -e 's,libprotobuf.a,protobuf,g'
+  '';
+
   free = stdenv.mkDerivation {
     name = "clementine-free-${version}";
-    inherit src patches nativeBuildInputs buildInputs;
+    inherit src patches nativeBuildInputs buildInputs postPatch;
 
     cmakeFlags = [ "-DUSE_SYSTEM_PROJECTM=ON" ];
 
     enableParallelBuilding = true;
-    postPatch = ''
-      sed -i src/CMakeLists.txt \
-        -e 's,-Werror,,g' \
-        -e 's,-Wno-unknown-warning-option,,g' \
-        -e 's,-Wno-unused-private-field,,g'
-    '';
+
     meta = with stdenv.lib; {
       homepage = http://www.clementine-player.org;
       description = "A multiplatform music player";
@@ -80,7 +84,7 @@ let
   blob = stdenv.mkDerivation {
     name = "clementine-blob-${version}";
     # Use the same patches and sources as Clementine
-    inherit src nativeBuildInputs;
+    inherit src nativeBuildInputs postPatch;
 
     patches = [
       ./clementine-spotify-blob.patch
diff --git a/pkgs/applications/misc/electrum-dash/default.nix b/pkgs/applications/misc/electrum-dash/default.nix
index 8752bafbe73..e7a5a1be197 100644
--- a/pkgs/applications/misc/electrum-dash/default.nix
+++ b/pkgs/applications/misc/electrum-dash/default.nix
@@ -13,7 +13,7 @@ python2Packages.buildPythonApplication rec {
     dns
     ecdsa
     pbkdf2
-    protobuf3_2
+    protobuf
     pyasn1
     pyasn1-modules
     pycrypto
diff --git a/pkgs/applications/misc/electrum-ltc/default.nix b/pkgs/applications/misc/electrum-ltc/default.nix
index 25c96322378..bb41f8665e5 100644
--- a/pkgs/applications/misc/electrum-ltc/default.nix
+++ b/pkgs/applications/misc/electrum-ltc/default.nix
@@ -20,7 +20,7 @@ python2Packages.buildPythonApplication rec {
     requests
     qrcode
     ltc_scrypt
-    protobuf3_2
+    protobuf
     dns
     jsonrpclib
   ];
diff --git a/pkgs/applications/misc/electrum/default.nix b/pkgs/applications/misc/electrum/default.nix
index b0f821a3aac..0781617eb69 100644
--- a/pkgs/applications/misc/electrum/default.nix
+++ b/pkgs/applications/misc/electrum/default.nix
@@ -14,7 +14,7 @@ python2Packages.buildPythonApplication rec {
     ecdsa
     jsonrpclib
     pbkdf2
-    protobuf3_2
+    protobuf
     pyaes
     pycrypto
     pyqt4
diff --git a/pkgs/applications/misc/ola/default.nix b/pkgs/applications/misc/ola/default.nix
index 0aba5106387..9db6042e60f 100644
--- a/pkgs/applications/misc/ola/default.nix
+++ b/pkgs/applications/misc/ola/default.nix
@@ -1,5 +1,5 @@
 { stdenv, fetchFromGitHub, autoreconfHook, bison, flex, pkgconfig
-, libuuid, cppunit, protobuf, zlib, avahi, libmicrohttpd
+, libuuid, cppunit, protobuf3_1, zlib, avahi, libmicrohttpd
 , perl, python3, python3Packages
 }:
 
@@ -15,8 +15,8 @@ stdenv.mkDerivation rec {
   };
 
   nativeBuildInputs = [ autoreconfHook bison flex pkgconfig perl ];
-  buildInputs = [ libuuid cppunit protobuf zlib avahi libmicrohttpd python3 ];
-  propagatedBuildInputs = with python3Packages; [ protobuf3_2 numpy ];
+  buildInputs = [ libuuid cppunit protobuf3_1 zlib avahi libmicrohttpd python3 ];
+  propagatedBuildInputs = [ python3Packages.protobuf3_1 python3Packages.numpy ];
 
   configureFlags = [ "--enable-python-libs" ];
 
diff --git a/pkgs/applications/networking/cluster/mesos/default.nix b/pkgs/applications/networking/cluster/mesos/default.nix
index 4c9753c1aac..16ef657111f 100644
--- a/pkgs/applications/networking/cluster/mesos/default.nix
+++ b/pkgs/applications/networking/cluster/mesos/default.nix
@@ -73,7 +73,7 @@ in stdenv.mkDerivation rec {
 
     substituteInPlace 3rdparty/stout/Makefile.am \
       --replace "-lprotobuf" \
-                "${pythonProtobuf.protobuf.lib}/lib/libprotobuf.a"
+                "${pythonProtobuf.protobuf}/lib/libprotobuf.so"
 
     substituteInPlace 3rdparty/stout/include/stout/os/posix/fork.hpp \
       --subst-var-by sh ${bash}/bin/bash
@@ -101,7 +101,7 @@ in stdenv.mkDerivation rec {
 
     substituteInPlace src/python/native_common/ext_modules.py.in \
       --replace "-lprotobuf" \
-                "${pythonProtobuf.protobuf.lib}/lib/libprotobuf.a"
+                "${pythonProtobuf.protobuf}/lib/libprotobuf.so"
 
     substituteInPlace src/slave/containerizer/mesos/isolators/gpu/volume.cpp \
       --subst-var-by cp    ${coreutils}/bin/cp \
@@ -126,7 +126,7 @@ in stdenv.mkDerivation rec {
     substituteInPlace src/Makefile.am \
       --subst-var-by mavenRepo ${mavenRepo} \
       --replace "-lprotobuf" \
-                "${pythonProtobuf.protobuf.lib}/lib/libprotobuf.a"
+                "${pythonProtobuf.protobuf}/lib/libprotobuf.so"
 
   '' + lib.optionalString stdenv.isLinux ''
 
diff --git a/pkgs/development/libraries/lightstep-tracer-cpp/default.nix b/pkgs/development/libraries/lightstep-tracer-cpp/default.nix
index e13796229ce..9aea42082c5 100644
--- a/pkgs/development/libraries/lightstep-tracer-cpp/default.nix
+++ b/pkgs/development/libraries/lightstep-tracer-cpp/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, lib, fetchFromGitHub, pkgconfig, protobuf3_2, automake
+{ stdenv, lib, fetchFromGitHub, pkgconfig, protobuf, automake
 , autoreconfHook, zlib
 , enableGrpc ? false
 }:
@@ -39,7 +39,7 @@ stdenv.mkDerivation rec {
   ];
 
   buildInputs = [
-    protobuf3_2 zlib
+    protobuf zlib
   ];
 
   meta = with lib; {
diff --git a/pkgs/development/libraries/opencv/3.x.nix b/pkgs/development/libraries/opencv/3.x.nix
index 69f0ce929d1..f6811b13717 100644
--- a/pkgs/development/libraries/opencv/3.x.nix
+++ b/pkgs/development/libraries/opencv/3.x.nix
@@ -8,7 +8,7 @@
 , enableJPEG2K    ? true, jasper
 
 , enableIpp       ? false
-, enableContrib   ? false, protobuf3_1
+, enableContrib   ? false, protobuf
 , enablePython    ? false, pythonPackages
 , enableGtk2      ? false, gtk2
 , enableGtk3      ? false, gtk3
@@ -146,7 +146,7 @@ stdenv.mkDerivation rec {
     # tesseract & leptonica.
     ++ lib.optionals enableTesseract [ tesseract leptonica ]
     ++ lib.optionals enableCuda [ cudatoolkit gcc5 ]
-    ++ lib.optional buildContrib protobuf3_1
+    ++ lib.optional buildContrib protobuf
     ++ lib.optionals stdenv.isDarwin [ AVFoundation Cocoa QTKit ];
 
   propagatedBuildInputs = lib.optional enablePython pythonPackages.numpy;
diff --git a/pkgs/development/libraries/protobuf/2.5.nix b/pkgs/development/libraries/protobuf/2.5.nix
deleted file mode 100644
index 9d7bb38cf3c..00000000000
--- a/pkgs/development/libraries/protobuf/2.5.nix
+++ /dev/null
@@ -1,10 +0,0 @@
-{ callPackage, fetchurl, ... } @ args:
-
-callPackage ./generic.nix (args // rec {
-  version = "2.5.0";
-  # make sure you test also -A pythonPackages.protobuf
-  src = fetchurl {
-    url = "http://protobuf.googlecode.com/files/${version}.tar.bz2";
-    sha256 = "0xxn9gxhvsgzz2sgmihzf6pf75clr05mqj6218camwrwajpcbgqk";
-  };
-})
diff --git a/pkgs/development/libraries/protobuf/2.6.nix b/pkgs/development/libraries/protobuf/2.6.nix
deleted file mode 100644
index 49ed9d9ade1..00000000000
--- a/pkgs/development/libraries/protobuf/2.6.nix
+++ /dev/null
@@ -1,12 +0,0 @@
-{ callPackage, fetchFromGitHub, ... } @ args:
-
-callPackage ./generic.nix (args // rec {
-  version = "2.6.1";
-  # make sure you test also -A pythonPackages.protobuf
-  src = fetchFromGitHub {
-    owner = "google";
-    repo = "protobuf";
-    rev = "v${version}";
-    sha256 = "03df8zvx2sry3jz2x4pi3l32qyfqa7w8kj8jdbz30nzy0h7aa070";
-  };
-})
diff --git a/pkgs/development/libraries/protobuf/3.0.0-beta-2.nix b/pkgs/development/libraries/protobuf/3.0.0-beta-2.nix
deleted file mode 100644
index 26b829669b8..00000000000
--- a/pkgs/development/libraries/protobuf/3.0.0-beta-2.nix
+++ /dev/null
@@ -1,6 +0,0 @@
-{ callPackage, ... }:
-
-callPackage ./generic-v3.nix {
-  version = "3.0.0-beta-2";
-  sha256 = "0cbr1glgma5vakabsjwcs41pcnn8yphhn037l0zd121zb9gdaqc1";
-}
diff --git a/pkgs/development/libraries/protobuf/3.0.nix b/pkgs/development/libraries/protobuf/3.0.nix
deleted file mode 100644
index 4e77e7f1fbe..00000000000
--- a/pkgs/development/libraries/protobuf/3.0.nix
+++ /dev/null
@@ -1,6 +0,0 @@
-{ callPackage, ... }:
-
-callPackage ./generic-v3.nix {
-  version = "3.0.2";
-  sha256 = "16wmr1fgdqpf84fkq90cxvccfsxx7h0q0wzqkbg8vdjmka412g09";
-}
diff --git a/pkgs/development/libraries/protobuf/3.2.nix b/pkgs/development/libraries/protobuf/3.2.nix
deleted file mode 100644
index 338156bbdf9..00000000000
--- a/pkgs/development/libraries/protobuf/3.2.nix
+++ /dev/null
@@ -1,6 +0,0 @@
-{ callPackage, lib, ... }:
-
-lib.overrideDerivation (callPackage ./generic-v3.nix {
-  version = "3.2.0";
-  sha256 = "120g0bg7ichry74allgmqnh7k0z2sdnrrfklb58b7szzn4zcdz14";
-}) (attrs: { NIX_CFLAGS_COMPILE = "-Wno-error"; })
diff --git a/pkgs/development/libraries/protobuf/3.3.nix b/pkgs/development/libraries/protobuf/3.4.nix
similarity index 61%
rename from pkgs/development/libraries/protobuf/3.3.nix
rename to pkgs/development/libraries/protobuf/3.4.nix
index e6a8f05cc18..75f1bb22c24 100644
--- a/pkgs/development/libraries/protobuf/3.3.nix
+++ b/pkgs/development/libraries/protobuf/3.4.nix
@@ -1,6 +1,6 @@
 { callPackage, lib, ... }:
 
 lib.overrideDerivation (callPackage ./generic-v3.nix {
-  version = "3.3.0";
-  sha256 = "1258yz9flyyaswh3izv227kwnhwcxn4nwavdz9iznqmh24qmi59w";
+  version = "3.4.0";
+  sha256 = "0385j54kgr71h0cxh5vqr81qs57ack2g2k9mcdbq188v4ckjacyx";
 }) (attrs: { NIX_CFLAGS_COMPILE = "-Wno-error"; })
diff --git a/pkgs/development/libraries/protobufc/1.0.nix b/pkgs/development/libraries/protobufc/1.0.nix
deleted file mode 100644
index d64ea5790c6..00000000000
--- a/pkgs/development/libraries/protobufc/1.0.nix
+++ /dev/null
@@ -1,11 +0,0 @@
-{ callPackage, fetchFromGitHub, ... } @ args:
-
-callPackage ./generic.nix (args // rec {
-  version = "1.0.2";
-  src = fetchFromGitHub {
-    owner = "protobuf-c";
-    repo = "protobuf-c";
-    rev = "v${version}";
-    sha256 = "1harabw7qdgcmh098664xkcv8bkyach6i35sisc40yhvagr3fzsz";
-  };
-})
diff --git a/pkgs/development/libraries/protobufc/1.1.nix b/pkgs/development/libraries/protobufc/1.1.nix
deleted file mode 100644
index 97fc8642778..00000000000
--- a/pkgs/development/libraries/protobufc/1.1.nix
+++ /dev/null
@@ -1,11 +0,0 @@
-{ callPackage, fetchFromGitHub, ... } @ args:
-
-callPackage ./generic.nix (args // rec {
-  version = "1.1.1";
-  src = fetchFromGitHub {
-    owner = "protobuf-c";
-    repo = "protobuf-c";
-    rev = "v${version}";
-    sha256 = "0mdl2i87394l4zdvq2npsxq4zs8p7sqhqmbm2r380ngjs6zic6gw";
-  };
-})
diff --git a/pkgs/development/python-modules/keepkey/default.nix b/pkgs/development/python-modules/keepkey/default.nix
index e54ed52d9c5..3e58e9e3e03 100644
--- a/pkgs/development/python-modules/keepkey/default.nix
+++ b/pkgs/development/python-modules/keepkey/default.nix
@@ -1,5 +1,5 @@
 { stdenv, fetchPypi, buildPythonPackage, ecdsa
-, mnemonic, protobuf3_2, hidapi }:
+, mnemonic, protobuf, hidapi }:
 
 buildPythonPackage rec {
   name = "${pname}-${version}";
@@ -11,7 +11,7 @@ buildPythonPackage rec {
     sha256 = "14d2r8dlx997ypgma2k8by90acw7i3l7hfq4gar9lcka0lqfj714";
   };
 
-  propagatedBuildInputs = [ protobuf3_2 hidapi ];
+  propagatedBuildInputs = [ protobuf hidapi ];
 
   buildInputs = [ ecdsa mnemonic ];
 
diff --git a/pkgs/development/python-modules/tensorflow/default.nix b/pkgs/development/python-modules/tensorflow/default.nix
index 388d27e0686..b8fb107968b 100644
--- a/pkgs/development/python-modules/tensorflow/default.nix
+++ b/pkgs/development/python-modules/tensorflow/default.nix
@@ -8,7 +8,7 @@
 , linuxPackages ? null
 , numpy
 , six
-, protobuf3_2
+, protobuf
 , swig
 , werkzeug
 , mock
@@ -94,7 +94,7 @@ buildPythonPackage rec {
     );
 
   propagatedBuildInputs = with stdenv.lib;
-    [ numpy six protobuf3_2 swig werkzeug mock ]
+    [ numpy six protobuf swig werkzeug mock ]
     ++ optionals cudaSupport [ cudatoolkit cudnn stdenv.cc ];
 
   # Note that we need to run *after* the fixup phase because the
diff --git a/pkgs/development/python-modules/trezor/default.nix b/pkgs/development/python-modules/trezor/default.nix
index 72d73022cab..c473403f53d 100644
--- a/pkgs/development/python-modules/trezor/default.nix
+++ b/pkgs/development/python-modules/trezor/default.nix
@@ -1,4 +1,4 @@
-{ lib, fetchPypi, buildPythonPackage, protobuf3_2, hidapi, ecdsa, mnemonic
+{ lib, fetchPypi, buildPythonPackage, protobuf, hidapi, ecdsa, mnemonic
 , requests
 }:
 
@@ -12,7 +12,7 @@ buildPythonPackage rec {
     sha256 = "6bdb69fc125ba705854e21163be6c7da3aa17c2a3a84f40b6d8a3f6e4a8cb314";
   };
 
-  propagatedBuildInputs = [ protobuf3_2 hidapi requests ];
+  propagatedBuildInputs = [ protobuf hidapi requests ];
 
   buildInputs = [ ecdsa mnemonic ];
 
diff --git a/pkgs/tools/networking/envoy/default.nix b/pkgs/tools/networking/envoy/default.nix
index 79a24ea1f8d..a4300c724e0 100644
--- a/pkgs/tools/networking/envoy/default.nix
+++ b/pkgs/tools/networking/envoy/default.nix
@@ -1,6 +1,6 @@
 { stdenv, lib, fetchFromGitHub, pkgconfig, bazel, c-ares, backward-cpp
 , libevent, gtest, gperftools, http-parser, lightstep-tracer-cpp
-, nghttp2, protobuf3_2, tclap, rapidjson, spdlog, boringssl, buildEnv
+, nghttp2, protobuf, tclap, rapidjson, spdlog, boringssl, buildEnv
 }:
 
 let
@@ -85,7 +85,7 @@ let
     };
 
     protobuf = {
-      pkg = protobuf3_2;
+      pkg = protobuf;
       srcs = ''glob(["lib/libproto*.so"])'';
       hdrs = ''glob(["include/google/protobuf/**/*.h"])'';
       includes = ''["include"]'';
@@ -201,7 +201,7 @@ let
     http-parser
     lightstep-tracer-cpp
     nghttp2
-    protobuf3_2
+    protobuf
     tclap
     rapidjson
     spdlog
diff --git a/pkgs/tools/networking/mitmproxy/default.nix b/pkgs/tools/networking/mitmproxy/default.nix
index db01b012a14..583100e0f37 100644
--- a/pkgs/tools/networking/mitmproxy/default.nix
+++ b/pkgs/tools/networking/mitmproxy/default.nix
@@ -63,7 +63,7 @@ in p.pkgs.buildPythonPackage rec {
   ];
 
   buildInputs = with p.pkgs; [
-    beautifulsoup4 flask pytz pytest pytestrunner protobuf3_2 glibcLocales
+    beautifulsoup4 flask pytz pytest pytestrunner protobuf glibcLocales
   ];
 
   meta = with stdenv.lib; {
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 4bb74400e6c..33532908ceb 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -1459,7 +1459,7 @@ with pkgs;
       clangStdenv = libcxxStdenv; # workaround for https://github.com/NixOS/nixpkgs/issues/28223
       python = python2;
       inherit (python2Packages) gyp;
-      protobuf = protobuf3_2.overrideDerivation (oldAttrs: { stdenv = clangStdenv; });
+      protobuf = pkgs.protobuf.overrideDerivation (oldAttrs: { stdenv = clangStdenv; });
     };
 
     table = callPackage ../tools/inputmethods/ibus-engines/ibus-table {
@@ -1946,7 +1946,7 @@ with pkgs;
       clangStdenv = libcxxStdenv; # workaround for https://github.com/NixOS/nixpkgs/issues/28223
       python = python2;
       inherit (python2Packages) gyp;
-      protobuf = protobuf3_2.overrideDerivation (oldAttrs: { stdenv = clangStdenv; });
+      protobuf = pkgs.protobuf.overrideDerivation (oldAttrs: { stdenv = clangStdenv; });
     };
 
     table-other = callPackage ../tools/inputmethods/fcitx-engines/fcitx-table-other { };
@@ -6360,7 +6360,7 @@ with pkgs;
   mesos = callPackage ../applications/networking/cluster/mesos {
     sasl = cyrus_sasl;
     inherit (pythonPackages) python boto setuptools wrapPython;
-    pythonProtobuf = pythonPackages.protobuf2_6;
+    pythonProtobuf = pythonPackages.protobuf;
     perf = linuxPackages.perf;
   };
 
@@ -9995,17 +9995,11 @@ with pkgs;
 
   postgis = callPackage ../development/libraries/postgis { };
 
-  protobuf = protobuf2_6;
-  protobuf3_0 = lowPrio (callPackage ../development/libraries/protobuf/3.0.nix { });
-  protobuf3_1 = callPackage ../development/libraries/protobuf/3.1.nix { };
-  protobuf3_2 = callPackage ../development/libraries/protobuf/3.2.nix { };
-  protobuf3_3 = callPackage ../development/libraries/protobuf/3.3.nix { };
-  protobuf2_6 = callPackage ../development/libraries/protobuf/2.6.nix { };
-  protobuf2_5 = callPackage ../development/libraries/protobuf/2.5.nix { };
+  protobuf = callPackage ../development/libraries/protobuf/3.4.nix { };
 
-  protobufc = protobufc1_1;
-  protobufc1_1 = callPackage ../development/libraries/protobufc/1.1.nix { };
-  protobufc1_0 = callPackage ../development/libraries/protobufc/1.0.nix { };
+  protobuf3_1 = callPackage ../development/libraries/protobuf/3.1.nix { };
+
+  protobufc = callPackage ../development/libraries/protobufc/1.3.nix { };
 
   flatbuffers = callPackage ../development/libraries/flatbuffers { };
 
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index bcb471b9f75..1587658063a 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -227,9 +227,7 @@ in {
 
   pycryptodomex = callPackage ../development/python-modules/pycryptodomex { };
 
-  PyChromecast = callPackage ../development/python-modules/pychromecast {
-    protobuf = self.protobuf3_2;
-  };
+  PyChromecast = callPackage ../development/python-modules/pychromecast { };
 
   pyexiv2 = if (!isPy3k) then callPackage ../development/python-modules/pyexiv2 {} else throw "pyexiv2 not supported for interpreter ${python.executable}";
 
@@ -5901,7 +5899,7 @@ in {
       validictory
       decorator
       mutagen
-      protobuf3_0
+      protobuf
       setuptools
       requests
       dateutil
@@ -7521,7 +7519,7 @@ in {
       sha256 = "09bf5gfip9x2wr0ij43p39ac6z2iqzn7kgpi2jjbwpnhs0vwkycs";
     };
 
-    propagatedBuildInputs = with self; [ python-axolotl-curve25519 protobuf3_0 pycrypto ];
+    propagatedBuildInputs = with self; [ python-axolotl-curve25519 protobuf pycrypto ];
     # IV == 0 in tests is not supported by pycrytpodom (our pycrypto drop-in)
     doCheck = !isPy3k;
 
@@ -16327,30 +16325,16 @@ in {
 
   });
 
-  protobuf = self.protobuf2_6;
-  protobuf3_3 = callPackage ../development/python-modules/protobuf.nix {
+  protobuf = callPackage ../development/python-modules/protobuf.nix {
     disabled = isPyPy;
     doCheck = !isPy3k;
-    protobuf = pkgs.protobuf3_3;
+    protobuf = pkgs.protobuf;
   };
-  protobuf3_2 = callPackage ../development/python-modules/protobuf.nix {
+
+  protobuf3_1 = callPackage ../development/python-modules/protobuf.nix {
     disabled = isPyPy;
     doCheck = !isPy3k;
-    protobuf = pkgs.protobuf3_2;
-  };
-  protobuf3_0 = callPackage ../development/python-modules/protobuf.nix {
-    disabled = isPyPy;
-    doCheck = !isPy3k;
-    protobuf = pkgs.protobuf3_0;
-  };
-  protobuf2_6 = callPackage ../development/python-modules/protobuf.nix {
-    disabled = isPy3k || isPyPy;
-    doCheck = false;
-    protobuf = pkgs.protobuf2_6;
-  };
-  protobuf2_5 = callPackage ../development/python-modules/protobuf.nix {
-    disabled = isPy3k || isPyPy;
-    protobuf = pkgs.protobuf2_5;
+    protobuf = pkgs.protobuf3_1;
   };
 
   psd-tools = callPackage ../development/python-modules/psd-tools { };
@@ -23876,9 +23860,7 @@ EOF
     inherit (pkgs) libasyncns pkgconfig;
   };
 
-  libarcus = callPackage ../development/python-modules/libarcus {
-    protobuf = self.protobuf3_0;
-  };
+  libarcus = callPackage ../development/python-modules/libarcus { };
 
   pybrowserid = buildPythonPackage rec {
     name = "PyBrowserID-${version}";
@@ -24160,7 +24142,7 @@ EOF
     '';
 
     buildInputs = with self; [ nose ];
-    propagatedBuildInputs = with self; [ noise numpy pyplatec protobuf3_2 purepng argparse h5py gdal ];
+    propagatedBuildInputs = with self; [ noise numpy pyplatec protobuf purepng argparse h5py gdal ];
 
     prePatch = ''
       substituteInPlace setup.py \