diff --git a/nixos/modules/services/desktops/gnome3/at-spi2-core.nix b/nixos/modules/services/desktops/gnome3/at-spi2-core.nix
index 22a54f511d1c..615f272e7b9a 100644
--- a/nixos/modules/services/desktops/gnome3/at-spi2-core.nix
+++ b/nixos/modules/services/desktops/gnome3/at-spi2-core.nix
@@ -4,6 +4,9 @@
 
 with lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -30,9 +33,9 @@ with lib;
 
   config = mkIf config.services.gnome3.at-spi2-core.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.at_spi2_core ];
+    environment.systemPackages = [ gnome3.at_spi2_core ];
 
-    services.dbus.packages = [ pkgs.gnome3.at_spi2_core ];
+    services.dbus.packages = [ gnome3.at_spi2_core ];
 
   };
 
diff --git a/nixos/modules/services/desktops/gnome3/gnome-documents.nix b/nixos/modules/services/desktops/gnome3/gnome-documents.nix
index 1f7592c0b417..2279ef48fb9c 100644
--- a/nixos/modules/services/desktops/gnome3/gnome-documents.nix
+++ b/nixos/modules/services/desktops/gnome3/gnome-documents.nix
@@ -4,6 +4,9 @@
 
 with pkgs.lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -30,9 +33,9 @@ with pkgs.lib;
 
   config = mkIf config.services.gnome3.gnome-documents.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.gnome-documents ];
+    environment.systemPackages = [ gnome3.gnome-documents ];
 
-    services.dbus.packages = [ pkgs.gnome3.gnome-documents ];
+    services.dbus.packages = [ gnome3.gnome-documents ];
 
     services.gnome3.gnome-online-accounts.enable = true;
 
diff --git a/nixos/modules/services/desktops/gnome3/gnome-keyring.nix b/nixos/modules/services/desktops/gnome3/gnome-keyring.nix
index 447fd783f148..be14f1fcbc0c 100644
--- a/nixos/modules/services/desktops/gnome3/gnome-keyring.nix
+++ b/nixos/modules/services/desktops/gnome3/gnome-keyring.nix
@@ -4,6 +4,9 @@
 
 with pkgs.lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -31,9 +34,9 @@ with pkgs.lib;
 
   config = mkIf config.services.gnome3.gnome-keyring.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.gnome_keyring ];
+    environment.systemPackages = [ gnome3.gnome_keyring ];
 
-    services.dbus.packages = [ pkgs.gnome3.gnome_keyring ];
+    services.dbus.packages = [ gnome3.gnome_keyring ];
 
   };
 
diff --git a/nixos/modules/services/desktops/gnome3/gnome-online-accounts.nix b/nixos/modules/services/desktops/gnome3/gnome-online-accounts.nix
index 365e19c15bb1..a41fb0101f0f 100644
--- a/nixos/modules/services/desktops/gnome3/gnome-online-accounts.nix
+++ b/nixos/modules/services/desktops/gnome3/gnome-online-accounts.nix
@@ -4,6 +4,9 @@
 
 with pkgs.lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -30,9 +33,9 @@ with pkgs.lib;
 
   config = mkIf config.services.gnome3.gnome-online-accounts.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.gnome_online_accounts ];
+    environment.systemPackages = [ gnome3.gnome_online_accounts ];
 
-    services.dbus.packages = [ pkgs.gnome3.gnome_online_accounts ];
+    services.dbus.packages = [ gnome3.gnome_online_accounts ];
 
   };
 
diff --git a/nixos/modules/services/desktops/gnome3/gnome-online-miners.nix b/nixos/modules/services/desktops/gnome3/gnome-online-miners.nix
index c921327a74ce..030d4bac6a76 100644
--- a/nixos/modules/services/desktops/gnome3/gnome-online-miners.nix
+++ b/nixos/modules/services/desktops/gnome3/gnome-online-miners.nix
@@ -4,6 +4,9 @@
 
 with pkgs.lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -30,9 +33,9 @@ with pkgs.lib;
 
   config = mkIf config.services.gnome3.gnome-online-miners.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.gnome-online-miners ];
+    environment.systemPackages = [ gnome3.gnome-online-miners ];
 
-    services.dbus.packages = [ pkgs.gnome3.gnome-online-miners ];
+    services.dbus.packages = [ gnome3.gnome-online-miners ];
 
   };
 
diff --git a/nixos/modules/services/desktops/gnome3/gnome-user-share.nix b/nixos/modules/services/desktops/gnome3/gnome-user-share.nix
index df796ed77ff4..3b6c713f7be3 100644
--- a/nixos/modules/services/desktops/gnome3/gnome-user-share.nix
+++ b/nixos/modules/services/desktops/gnome3/gnome-user-share.nix
@@ -4,6 +4,9 @@
 
 with pkgs.lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -30,9 +33,9 @@ with pkgs.lib;
 
   config = mkIf config.services.gnome3.gnome-user-share.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.gnome-user-share ];
+    environment.systemPackages = [ gnome3.gnome-user-share ];
 
-    services.xserver.displayManager.sessionCommands = with pkgs.gnome3; ''
+    services.xserver.displayManager.sessionCommands = with gnome3; ''
       # Don't let gnome-control-center depend upon gnome-user-share
       export XDG_DATA_DIRS=$XDG_DATA_DIRS''${XDG_DATA_DIRS:+:}${gnome-user-share}/share/gsettings-schemas/${gnome-user-share.name}
     '';
diff --git a/nixos/modules/services/desktops/gnome3/seahorse.nix b/nixos/modules/services/desktops/gnome3/seahorse.nix
index cad22a6a5983..01e4a24f2672 100644
--- a/nixos/modules/services/desktops/gnome3/seahorse.nix
+++ b/nixos/modules/services/desktops/gnome3/seahorse.nix
@@ -4,6 +4,9 @@
 
 with pkgs.lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -29,9 +32,9 @@ with pkgs.lib;
 
   config = mkIf config.services.gnome3.seahorse.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.seahorse ];
+    environment.systemPackages = [ gnome3.seahorse ];
 
-    services.dbus.packages = [ pkgs.gnome3.seahorse ];
+    services.dbus.packages = [ gnome3.seahorse ];
 
   };
 
diff --git a/nixos/modules/services/desktops/gnome3/sushi.nix b/nixos/modules/services/desktops/gnome3/sushi.nix
index 7a4389038b22..ff7f484602c7 100644
--- a/nixos/modules/services/desktops/gnome3/sushi.nix
+++ b/nixos/modules/services/desktops/gnome3/sushi.nix
@@ -4,6 +4,9 @@
 
 with lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -29,9 +32,9 @@ with lib;
 
   config = mkIf config.services.gnome3.sushi.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.sushi ];
+    environment.systemPackages = [ gnome3.sushi ];
 
-    services.dbus.packages = [ pkgs.gnome3.sushi ];
+    services.dbus.packages = [ gnome3.sushi ];
 
   };
 
diff --git a/nixos/modules/services/desktops/gnome3/tracker.nix b/nixos/modules/services/desktops/gnome3/tracker.nix
index 94a22d0c8819..670e585c6f55 100644
--- a/nixos/modules/services/desktops/gnome3/tracker.nix
+++ b/nixos/modules/services/desktops/gnome3/tracker.nix
@@ -4,6 +4,9 @@
 
 with pkgs.lib;
 
+let
+  gnome3 = config.environment.gnome3.packageSet;
+in
 {
 
   ###### interface
@@ -30,9 +33,9 @@ with pkgs.lib;
 
   config = mkIf config.services.gnome3.tracker.enable {
 
-    environment.systemPackages = [ pkgs.gnome3.tracker ];
+    environment.systemPackages = [ gnome3.tracker ];
 
-    services.dbus.packages = [ pkgs.gnome3.tracker ];
+    services.dbus.packages = [ gnome3.tracker ];
 
   };
 
diff --git a/nixos/modules/services/x11/desktop-managers/gnome3.nix b/nixos/modules/services/x11/desktop-managers/gnome3.nix
index 3f48035f6bba..63f39ec0d3af 100644
--- a/nixos/modules/services/x11/desktop-managers/gnome3.nix
+++ b/nixos/modules/services/x11/desktop-managers/gnome3.nix
@@ -4,13 +4,13 @@ with lib;
 
 let
   cfg = config.services.xserver.desktopManager.gnome3;
-  gnome3 = pkgs.gnome3;
+  gnome3 = config.environment.gnome3.packageSet;
 
   # Remove packages of ys from xs, based on their names
   removePackagesByName = xs: ys:
     let
       pkgName = drv: (builtins.parseDrvName drv.name).name;
-	  ysNames = map pkgName ys;
+      ysNames = map pkgName ys;
       res = (filter (x: !(builtins.elem (pkgName x) ysNames)) xs);
     in
       filter (x: !(builtins.elem (pkgName x) ysNames)) xs;
@@ -35,6 +35,12 @@ in {
       description = "Enable Gnome 3 desktop manager.";
     };
 
+    environment.gnome3.packageSet = mkOption {
+      default = pkgs.gnome3;
+      example = literalExample "pkgs.gnome3_12";
+      description = "Which Gnome 3 package set to use.";
+    };
+    
     environment.gnome3.excludePackages = mkOption {
       default = [];
       example = "[ pkgs.gnome3.totem ]";
@@ -80,7 +86,7 @@ in {
 
           # Don't let epiphany depend upon gnome-shell
           # Override default mimeapps
-          export XDG_DATA_DIRS=$XDG_DATA_DIRS''${XDG_DATA_DIRS:+:}${pkgs.gnome3.gnome_shell}/share/gsettings-schemas/${pkgs.gnome3.gnome_shell.name}:${mimeAppsList}/share
+          export XDG_DATA_DIRS=$XDG_DATA_DIRS''${XDG_DATA_DIRS:+:}${gnome3.gnome_shell}/share/gsettings-schemas/${gnome3.gnome_shell.name}:${mimeAppsList}/share
 
           # Let gnome-control-center find gnome-shell search providers
           export GNOME_SEARCH_PROVIDERS_DIR=${config.system.path}/share/gnome-shell/search-providers/