diff --git a/pkgs/build-support/vm/default.nix b/pkgs/build-support/vm/default.nix
index cfc19c03cfdd..3a52d756571c 100644
--- a/pkgs/build-support/vm/default.nix
+++ b/pkgs/build-support/vm/default.nix
@@ -494,7 +494,9 @@ rec {
      tarball must contain an RPM specfile. */
 
   buildRPM = attrs: runInLinuxImage (stdenv.mkDerivation ({
-    phases = "prepareImagePhase sysInfoPhase buildPhase installPhase";
+    prePhases = [ prepareImagePhase sysInfoPhase ];
+    dontUnpack = true;
+    dontConfigure = true;
 
     outDir = "rpms/${attrs.diskImage.name}";
 
diff --git a/pkgs/build-support/vm/test.nix b/pkgs/build-support/vm/test.nix
index 698503032671..1a29554ee80c 100644
--- a/pkgs/build-support/vm/test.nix
+++ b/pkgs/build-support/vm/test.nix
@@ -1,4 +1,4 @@
-with import ../../.. {};
+with import ../../.. { };
 with vmTools;
 
 {
@@ -30,7 +30,7 @@ with vmTools;
     src = patchelf.src;
     diskImage = diskImages.ubuntu1204i386;
     memSize = 512;
-    phases = "sysInfoPhase unpackPhase patchPhase configurePhase buildPhase checkPhase installPhase fixupPhase distPhase";
+    prePhases = [ sysInfoPhase ];
     sysInfoPhase = ''
       dpkg-query --list
     '';