diff --git a/pkgs/applications/networking/irc/quassel/default.nix b/pkgs/applications/networking/irc/quassel/default.nix
index 0c89b002f47c..f48309d0b049 100644
--- a/pkgs/applications/networking/irc/quassel/default.nix
+++ b/pkgs/applications/networking/irc/quassel/default.nix
@@ -22,17 +22,13 @@ assert !buildClient -> !withKDE; # KDE is used by the client only
 
 let
   edf = flag: feature: [("-D" + feature + (if flag then "=ON" else "=OFF"))];
+  source = import ./source.nix { inherit fetchurl; };
 
 in with stdenv; mkDerivation rec {
+  inherit (source) src version;
 
-  version = "0.12.3";
   name = "quassel${tag}-${version}";
 
-  src = fetchurl {
-    url = "http://quassel-irc.org/pub/quassel-${version}.tar.bz2";
-    sha256 = "15vqjiw38mifvnc95bhvy0zl23xxldkwg2byx9xqbyw8rfgggmkb";
-  };
-
   enableParallelBuilding = true;
 
   buildInputs =
diff --git a/pkgs/applications/networking/irc/quassel/qt-5.nix b/pkgs/applications/networking/irc/quassel/qt-5.nix
index f401cace06ec..c80624ac0510 100644
--- a/pkgs/applications/networking/irc/quassel/qt-5.nix
+++ b/pkgs/applications/networking/irc/quassel/qt-5.nix
@@ -33,25 +33,13 @@ assert !buildClient -> !withKDE; # KDE is used by the client only
 
 let
   edf = flag: feature: [("-D" + feature + (if flag then "=ON" else "=OFF"))];
+  source = import ./source.nix { inherit fetchurl; };
 
 in with stdenv; mkDerivation rec {
+  inherit (source) src version;
 
-  version = "0.12.3";
   name = "quassel${tag}-${version}";
 
-  src = fetchurl {
-    url = "http://quassel-irc.org/pub/quassel-${version}.tar.bz2";
-    sha256 = "15vqjiw38mifvnc95bhvy0zl23xxldkwg2byx9xqbyw8rfgggmkb";
-  };
-
-  patches = [
-    # fix build with Qt 5.5
-    (fetchurl {
-      url = "https://github.com/quassel/quassel/commit/078477395aaec1edee90922037ebc8a36b072d90.patch";
-      sha256 = "1njwnay7pjjw0g7m0x5cwvck8xcznc7jbdfyhbrd121nc7jgpbc5";
-    })
-  ];
-
   enableParallelBuilding = true;
 
   buildInputs =
diff --git a/pkgs/applications/networking/irc/quassel/source.nix b/pkgs/applications/networking/irc/quassel/source.nix
new file mode 100644
index 000000000000..17d12b575d75
--- /dev/null
+++ b/pkgs/applications/networking/irc/quassel/source.nix
@@ -0,0 +1,9 @@
+{ fetchurl }:
+
+rec {
+  version = "0.12.3";
+  src = fetchurl {
+    url = "http://quassel-irc.org/pub/quassel-${version}.tar.bz2";
+    sha256 = "0d6lwf6qblj1ia5j9mjy112zrmpbbg9mmxgscbgxiqychldyjgjd";
+  };
+}