diff --git a/lib/test-driver/test-driver.pl b/lib/test-driver/test-driver.pl
index 362572205242..77df6cd2bd2c 100644
--- a/lib/test-driver/test-driver.pl
+++ b/lib/test-driver/test-driver.pl
@@ -1,4 +1,4 @@
-#! /somewhere/perl
+#! /somewhere/perl -w
 
 use strict;
 use Machine;
@@ -10,13 +10,23 @@ $SIG{PIPE} = 'IGNORE'; # because Unix domain sockets may die unexpectedly
 
 STDERR->autoflush(1);
 
+my $logFile = defined $ENV{LOGFILE} ? "$ENV{LOGFILE}" : "/dev/null";
+my $log = new XML::Writer(OUTPUT => new IO::File(">$logFile"));
+$log->startTag("logfile");
+
 
 my %vms;
 my $context = "";
 
-foreach my $vmScript (@ARGV) {
-    my $vm = Machine->new({startCommand => $vmScript});
+sub createMachine {
+    my ($args) = @_;
+    my $vm = Machine->new($args);
     $vms{$vm->name} = $vm;
+    return $vm;
+}
+
+foreach my $vmScript (@ARGV) {
+    my $vm = createMachine({startCommand => $vmScript});
     $context .= "my \$" . $vm->name . " = \$vms{'" . $vm->name . "'}; ";
 }
 
@@ -86,6 +96,8 @@ END {
             kill 9, $vm->{pid};
         }
     }
+    $log->endTag("logfile");
+    $log->end;
 }
 
 
diff --git a/lib/testing.nix b/lib/testing.nix
index 46ca9954ccde..4d1c389de488 100644
--- a/lib/testing.nix
+++ b/lib/testing.nix
@@ -50,7 +50,7 @@ rec {
         ''
           ensureDir $out/nix-support
 
-          ${testDriver}/bin/nixos-test-driver ${network}/vms/*/bin/run-*-vm
+          LOGFILE=$out/log.xml ${testDriver}/bin/nixos-test-driver ${network}/vms/*/bin/run-*-vm
           
           for i in */coverage-data; do
             ensureDir $out/coverage-data
diff --git a/tests/installer.nix b/tests/installer.nix
index 994d1173c2d0..f4d4281a0736 100644
--- a/tests/installer.nix
+++ b/tests/installer.nix
@@ -93,7 +93,7 @@ let
     ''
       createDisk("harddisk", 4 * 1024);
 
-      my $machine = Machine->new({ hda => "harddisk", cdrom => glob("${iso}/iso/*.iso"), qemuFlags => '${qemuNICFlags 1 1 1}' });
+      my $machine = createMachine({ hda => "harddisk", cdrom => glob("${iso}/iso/*.iso"), qemuFlags => '${qemuNICFlags 1 1 1}' });
       $machine->start;
 
       ${optionalString testChannel ''
@@ -158,7 +158,7 @@ let
       $machine->shutdown;
 
       # Now see if we can boot the installation.
-      my $machine = Machine->new({ hda => "harddisk" });
+      my $machine = createMachine({ hda => "harddisk" });
       
       # Did /boot get mounted, if appropriate?
       # !!! There is currently no good way to wait for the
@@ -181,7 +181,7 @@ let
 
       # And just to be sure, check that the machine still boots after
       # "nixos-rebuild switch".
-      my $machine = Machine->new({ hda => "harddisk" });
+      my $machine = createMachine({ hda => "harddisk" });
       $machine->mustSucceed("echo hello");
       $machine->shutdown;
     '';
@@ -304,7 +304,7 @@ in {
       testScript =
         ''
           # damn, it's costly to evaluate nixos-rebuild (1G of ram)
-          my $machine = Machine->new({ cdrom => glob("${iso}/iso/*.iso"), qemuFlags => '${qemuNICFlags 1 1 1} -m 1024' });
+          my $machine = createMachine({ cdrom => glob("${iso}/iso/*.iso"), qemuFlags => '${qemuNICFlags 1 1 1} -m 1024' });
           $machine->start;
 
           # Make sure that we don't try to download anything.