diff --git a/default.nix b/default.nix
index 30eff6c2e6a5..ebb9110eb355 100644
--- a/default.nix
+++ b/default.nix
@@ -8,27 +8,39 @@ let
   
   nixpkgs = fromEnv "NIXPKGS" /etc/nixos/nixpkgs;
 
-  system = import system/system.nix { inherit configuration nixpkgs; };
+  pkgs = import nixpkgs {system = builtins.currentSystem;};
+  
+  #system = import system/system.nix { inherit configuration nixpkgs; };
 
+  configComponents = [
+    configuration
+    (import ./system/options.nix)
+  ];
+
+  # Make a configuration object from which we can retrieve option
+  # values.
+  config =
+    pkgs.lib.fixOptionSets
+      pkgs.lib.mergeOptionSets
+      pkgs configComponents;
+
+  optionDeclarations =
+    pkgs.lib.fixOptionSetsFun
+      pkgs.lib.filterOptionSets
+      pkgs configComponents
+      config;
+  
 in
 
-{ inherit (system)
-    activateConfiguration
-    bootStage2
-    etc
-    grubMenuBuilder
-    kernel
-    modulesTree
-    system
-    systemPath
-    config
-    ;
+{
 
-  nix = system.config.environment.nix;
+  system = config.system.build.system;
+
+  nix = config.environment.nix;
   
-  nixFallback = (import nixpkgs {}).nixUnstable;
+  nixFallback = pkgs.nixUnstable;
 
-  manifests = system.config.installer.manifests; # exported here because nixos-rebuild uses it
+  manifests = config.installer.manifests; # exported here because nixos-rebuild uses it
 
-  tests = system.config.tests;
+  tests = config.tests;
 }
diff --git a/system/switch-to-configuration.sh b/modules/system/activation/switch-to-configuration.sh
similarity index 100%
rename from system/switch-to-configuration.sh
rename to modules/system/activation/switch-to-configuration.sh
diff --git a/modules/system/activation/top-level.nix b/modules/system/activation/top-level.nix
new file mode 100644
index 000000000000..306037d1f575
--- /dev/null
+++ b/modules/system/activation/top-level.nix
@@ -0,0 +1,83 @@
+{pkgs, config, ...}:
+
+let
+
+  # This attribute is responsible for creating boot entries for 
+  # child configuration. They are only (directly) accessible
+  # when the parent configuration is boot default. For example,
+  # you can provide an easy way to boot the same configuration 
+  # as you use, but with another kernel
+  # !!! fix this
+  children = map (x: ((import ./system.nix)
+    { platform = pkgs.system;
+      configuration = x//{boot=((x.boot)//{grubDevice = "";});};}).system) 
+    config.nesting.children;
+
+
+  systemBuilder =
+    ''
+      ensureDir $out
+
+      ln -s ${config.boot.kernelPackages.kernel}/vmlinuz $out/kernel
+      ln -s $grub $out/grub
+      ln -s ${config.system.build.bootStage2} $out/init
+      ln -s ${config.system.build.initialRamdisk}/initrd $out/initrd
+      ln -s ${config.system.activationScripts.script} $out/activate
+      ln -s ${config.system.build.etc}/etc $out/etc
+      ln -s ${config.system.path} $out/sw
+      ln -s ${pkgs.upstart} $out/upstart
+
+      echo "$kernelParams" > $out/kernel-params
+      echo "$configurationName" > $out/configuration-name
+      echo "${toString pkgs.upstart.interfaceVersion}" > $out/upstart-interface-version
+
+      mkdir $out/fine-tune
+      childCount=0;
+      for i in $children; do 
+        childCount=$(( childCount + 1 ));
+        ln -s $i $out/fine-tune/child-$childCount;
+      done
+
+      cat > $out/menu.lst << GRUBEND
+      kernel $kernel init=$bootStage2 $kernelParams
+      initrd $initrd
+      GRUBEND
+
+      ensureDir $out/bin
+      substituteAll ${./switch-to-configuration.sh} $out/bin/switch-to-configuration
+      chmod +x $out/bin/switch-to-configuration
+    '';
+
+  
+  # Putting it all together.  This builds a store path containing
+  # symlinks to the various parts of the built configuration (the
+  # kernel, the Upstart services, the init scripts, etc.) as well as a
+  # script `switch-to-configuration' that activates the configuration
+  # and makes it bootable.
+  system = pkgs.stdenv.mkDerivation {
+    name = "system";
+    buildCommand = systemBuilder;
+    inherit children;
+    inherit (pkgs) grub;
+    grubDevice = config.boot.grubDevice;
+    kernelParams =
+      config.boot.kernelParams ++ config.boot.extraKernelParams;
+    grubMenuBuilder = config.system.build.grubMenuBuilder;
+    configurationName = config.boot.configurationName;
+    # Most of these are needed by grub-install.
+    path = [
+      pkgs.coreutils
+      pkgs.gnused
+      pkgs.gnugrep
+      pkgs.findutils
+      pkgs.diffutils
+      pkgs.upstart # for initctl
+    ];
+  };
+
+
+in {
+
+  system.build.system = system;
+
+}
diff --git a/system/options.nix b/system/options.nix
index 90add193c863..a15a4b30a4a5 100644
--- a/system/options.nix
+++ b/system/options.nix
@@ -445,6 +445,7 @@ in
     ../modules/services/x11/xfs.nix
     ../modules/services/x11/xserver/default.nix
     ../modules/system/activation/activation-script.nix
+    ../modules/system/activation/top-level.nix
     ../modules/system/boot/kernel.nix
     ../modules/system/boot/stage-1.nix
     ../modules/system/boot/stage-2.nix
diff --git a/system/system.nix b/system/system.nix
deleted file mode 100644
index ee9c6d259342..000000000000
--- a/system/system.nix
+++ /dev/null
@@ -1,75 +0,0 @@
-{ platform ? __currentSystem
-, configuration
-, nixpkgs ? ../../nixpkgs
-}:
-
-rec {
-
-  configComponents = [
-    configuration
-    (import ./options.nix)
-  ];
-
-  # Make a configuration object from which we can retrieve option
-  # values.
-  config =
-    pkgs.lib.fixOptionSets
-      pkgs.lib.mergeOptionSets
-      pkgs configComponents;
-
-  optionDeclarations =
-    pkgs.lib.fixOptionSetsFun
-      pkgs.lib.filterOptionSets
-      pkgs configComponents
-      config;
-
-  pkgs = import nixpkgs {system = platform;};
-
-
-  # This attribute is responsible for creating boot entries for 
-  # child configuration. They are only (directly) accessible
-  # when the parent configuration is boot default. For example,
-  # you can provide an easy way to boot the same configuration 
-  # as you use, but with another kernel
-  children = map (x: ((import ./system.nix)
-    { inherit platform; 
-      configuration = x//{boot=((x.boot)//{grubDevice = "";});};}).system) 
-    config.nesting.children; 
-
-  
-  # Putting it all together.  This builds a store object containing
-  # symlinks to the various parts of the built configuration (the
-  # kernel, the Upstart services, the init scripts, etc.) as well as a
-  # script `switch-to-configuration' that activates the configuration
-  # and makes it bootable.
-  system = pkgs.checker (pkgs.stdenv.mkDerivation {
-    name = "system";
-    builder = ./system.sh;
-    switchToConfiguration = ./switch-to-configuration.sh;
-    inherit (pkgs) grub upstart;
-    grubDevice = config.boot.grubDevice;
-    kernelParams =
-      config.boot.kernelParams ++ config.boot.extraKernelParams;
-    bootStage2 = config.system.build.bootStage2;
-    activateConfiguration = config.system.activationScripts.script;
-    grubMenuBuilder = config.system.build.grubMenuBuilder;
-    etc = config.system.build.etc;
-    systemPath = config.system.path;
-    inherit children;
-    configurationName = config.boot.configurationName;
-    kernel = config.boot.kernelPackages.kernel + "/vmlinuz";
-    initrd = config.system.build.initialRamdisk + "/initrd";
-    # Most of these are needed by grub-install.
-    path = [
-      pkgs.coreutils
-      pkgs.gnused
-      pkgs.gnugrep
-      pkgs.findutils
-      pkgs.diffutils
-      pkgs.upstart # for initctl
-    ];
-    upstartInterfaceVersion = pkgs.upstart.interfaceVersion;
-  }) config.environment.checkConfigurationOptions
-     optionDeclarations config;
-
-}
diff --git a/system/system.sh b/system/system.sh
deleted file mode 100644
index 67042b5faf45..000000000000
--- a/system/system.sh
+++ /dev/null
@@ -1,32 +0,0 @@
-source $stdenv/setup
-
-ensureDir $out
-
-ln -s $kernel $out/kernel
-ln -s $grub $out/grub
-ln -s $bootStage2 $out/init
-ln -s $initrd $out/initrd
-ln -s $activateConfiguration $out/activate
-ln -s $etc/etc $out/etc
-ln -s $systemPath $out/sw
-ln -s $upstart $out/upstart
-
-echo "$kernelParams" > $out/kernel-params
-echo "$configurationName" > $out/configuration-name
-echo "$upstartInterfaceVersion" > $out/upstart-interface-version
-
-mkdir $out/fine-tune
-ChildCount=0;
-for i in $children; do 
-	ChildCount=$(( ChildCount + 1 ));
-	ln -s $i $out/fine-tune/child-$ChildCount;
-done
-
-cat > $out/menu.lst << GRUBEND
-kernel $kernel init=$bootStage2 $kernelParams
-initrd $initrd
-GRUBEND
-
-ensureDir $out/bin
-substituteAll $switchToConfiguration $out/bin/switch-to-configuration
-chmod +x $out/bin/switch-to-configuration