diff --git a/test/installer.sh b/test/installer.sh
index 359086a5238..14b6e2a4aac 100644
--- a/test/installer.sh
+++ b/test/installer.sh
@@ -31,7 +31,7 @@ umount "$targetDevice" 2> /dev/null || true
 
 
 # Check it.
-fsck "$targetDevice"
+fsck -n "$targetDevice"
 
 
 # Mount the target device.
@@ -107,7 +107,7 @@ cp /etc/resolv.conf $mountPoint/etc/
 
 # Do a nix-pull to speed up building.
 nixpkgsURL=http://nix.cs.uu.nl/dist/nix/nixpkgs-0.11pre6984
-chroot $mountPoint @nix@/bin/nix-pull $nixpkgsURL/MANIFEST
+#chroot $mountPoint @nix@/bin/nix-pull $nixpkgsURL/MANIFEST
 
 
 # Build the specified Nix expression in the target store and install
@@ -120,4 +120,15 @@ chroot $mountPoint @nix@/bin/nix-pull $nixpkgsURL/MANIFEST
 
 chroot $mountPoint @nix@/bin/nix-env \
     -p /nix/var/nix/profiles/system \
-    -f "/mnt/$nixExpr" -i '*'
+    -f "/mnt/$nixExpr" -i system-configuration
+
+
+# Grub needs a mtab.
+echo "$targetDevice / somefs rw 0 0" > $mountPoint/etc/mtab
+
+
+# Switch to the new system configuration.  This will install Grub with
+# a menu default pointing at the kernel/initrd/etc of the new
+# configuration.
+echo "finalising the installation..."
+chroot $mountPoint /nix/var/nix/profiles/system/bin/switch-to-configuration
diff --git a/test/make-initrd.nix b/test/make-initrd.nix
index f850e1cf657..91722b96602 100644
--- a/test/make-initrd.nix
+++ b/test/make-initrd.nix
@@ -10,11 +10,11 @@
 # A symlink `/init' is made to the store path passed in the `init'
 # argument.
 
-{stdenv, cpio, packages, init}:
+{stdenv, cpio, packages, init, nix}:
 
 stdenv.mkDerivation {
   name = "initrd";
   builder = ./make-initrd.sh;
-  buildInputs = [cpio];
+  buildInputs = [cpio nix];
   inherit packages init;
 }
diff --git a/test/make-initrd.sh b/test/make-initrd.sh
index 2620b90eec7..5da23533feb 100644
--- a/test/make-initrd.sh
+++ b/test/make-initrd.sh
@@ -6,7 +6,7 @@ set -o pipefail
 # way to get the closure is to call Nix, which is strictly speaking
 # forbidden.  But we do it anyway.  In time, we should add a feature
 # to Nix to let Nix pass closures to builders.
-packagesClosure=$(/nix/bin/nix-store -qR $packages $init)
+packagesClosure=$(nix-store -qR $packages $init)
 
 # Paths in cpio archives *must* be relative, otherwise the kernel
 # won't unpack 'em.
diff --git a/test/rescue-cd.nix b/test/rescue-cd.nix
index defeeb48ece..002288bea87 100644
--- a/test/rescue-cd.nix
+++ b/test/rescue-cd.nix
@@ -14,6 +14,8 @@ in
   
 rec {
 
+  inherit nixosInstaller; # !!! debug
+
 
   # Since the CD is read-only, the mount points must be on disk.
   cdMountPoints = pkgs.stdenv.mkDerivation {
diff --git a/test/rescue-system.nix b/test/rescue-system.nix
index 890e3cfdf82..40ec535c6b1 100644
--- a/test/rescue-system.nix
+++ b/test/rescue-system.nix
@@ -59,7 +59,7 @@ rec {
   # The closure of the init script of boot stage 1 is what we put in
   # the initial RAM disk.
   initialRamdisk = import ./make-initrd.nix {
-    inherit (pkgs) stdenv cpio;
+    inherit (pkgs) stdenv cpio nix;
     packages = [];
     init = bootStage1;
   };
diff --git a/test/system-configuration.nix b/test/system-configuration.nix
new file mode 100644
index 00000000000..ef04dc1badc
--- /dev/null
+++ b/test/system-configuration.nix
@@ -0,0 +1,32 @@
+let
+
+  # The root device.
+  rootDevice = "/dev/hda1";
+
+  # The device on which GRUB should be installed (leave empty if you
+  # don't want GRUB to be installed).
+  grubDevice = "/dev/hda";
+
+in
+
+  # Build boot scripts for the CD that find the CD-ROM automatically.
+  with import ./rescue-system.nix {
+    autoDetectRootDevice = false;
+    inherit rootDevice;
+  };
+
+  
+rec {
+
+
+  systemConfiguration = pkgs.stdenv.mkDerivation {
+    name = "system-configuration";
+    builder = ./system-configuration.sh;
+    inherit (pkgs) grub coreutils gnused gnugrep diffutils;
+    inherit grubDevice;
+    kernel = pkgs.kernel + "/vmlinuz";
+    initrd = initialRamdisk + "/initrd";
+  };
+
+
+}
diff --git a/test/system-configuration.sh b/test/system-configuration.sh
new file mode 100644
index 00000000000..17d58f4d0cb
--- /dev/null
+++ b/test/system-configuration.sh
@@ -0,0 +1,29 @@
+source $stdenv/setup
+
+ensureDir $out
+
+ln -s $kernel $out/kernel
+ln -s $grub $out/grub
+
+cat > $out/menu.lst << GRUBEND
+# Automatically generated.  DO NOT EDIT THIS FILE!
+default=0
+timeout=5
+title NixOS
+        kernel $kernel selinux=0 apm=on acpi=on
+        initrd $initrd
+GRUBEND
+
+ensureDir $out/bin
+
+cat > $out/bin/switch-to-configuration <<EOF
+#! $SHELL
+set -e
+export PATH=$coreutils/bin:$gnused/bin:$gnugrep/bin:$diffutils/bin
+if test -n "$grubDevice"; then
+    $grub/sbin/grub-install "$grubDevice" --no-floppy --recheck
+    cp -f $out/menu.lst /boot/grub/menu.lst
+fi
+EOF
+
+chmod +x $out/bin/switch-to-configuration