diff --git a/config b/config
index a6c722c..3f2ede6 100644
--- a/config
+++ b/config
@@ -76,6 +76,7 @@ base_packages=(
 	zsh
 	rsync
 	git-core
+	mlocate
 )
 
 purge_packages+=(
diff --git a/libdevuansdk b/libdevuansdk
index 1851096..40eb799 100644
--- a/libdevuansdk
+++ b/libdevuansdk
@@ -17,7 +17,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this source code. If not, see <http://www.gnu.org/licenses/>.
 
-libdevuansdk_version="0.4"
+libdevuansdk_version="0.5"
 LIBPATH=${LIBPATH:-$(dirname $0)}
 
 source $LIBPATH/config
diff --git a/zlibs/bootstrap b/zlibs/bootstrap
index ff294eb..a2ef358 100644
--- a/zlibs/bootstrap
+++ b/zlibs/bootstrap
@@ -151,6 +151,19 @@ bootstrap_tar_unpack() {
 	cat <<EOF | sudo tee ${strapdir}/postunpack >/dev/null
 #!/bin/sh
 apt-get update
+
+## check if all our extra_packages exist
+allpkgs="\$(apt-cache search '.' | cut -d' ' -f1)"
+for i in ${extra_packages} ; do
+	printf "%s" "\$allpkgs" | grep -q "^\$i$" || missing="\$missing \$i"
+done
+
+[ -n "\$missing" ] && {
+	printf "\033[1;31m[!!] some extra packages don't exist\033[0m\n"
+	printf "%s\n" "\$missing"
+	exit 1
+}
+
 apt-get --yes --force-yes upgrade
 apt-get --yes --force-yes install ${extra_packages}
 apt-get --yes --force-yes autoremove
diff --git a/zlibs/imaging b/zlibs/imaging
index 03e7af9..b508915 100644
--- a/zlibs/imaging
+++ b/zlibs/imaging
@@ -114,10 +114,12 @@ image_pack_dist() {
 		zerr
 	}
 
-	notice "compressing image with xz"
+	_xz="xz -zv"
+	[[ $(command -v pixz) ]] && _xz=pixz
+	notice "compressing image with $_xz"
 	silly
 	pushd $workdir
-	xz -zv ${image_name}.img
+	${=_xz} ${image_name}.img
 
 	notice "generating sha256 for ${image_name}.img.xz"
 	sha256sum ${image_name}.img.xz > ${image_name}.img.xz.sha
@@ -143,9 +145,11 @@ image_raw_mount() {
 	sudo mount $rootpart $workdir/mnt && \
 		act "mounted root partition" || zerr
 
-	sudo mkdir $workdir/mnt/boot
-	sudo mount $bootpart $workdir/mnt/boot && \
-		act "mounted boot partition" || zerr
+	[[ "$parted_type" == gpt ]] || {
+		sudo mkdir $workdir/mnt/boot
+		sudo mount $bootpart $workdir/mnt/boot && \
+			act "mounted boot partition" || zerr
+	}
 }
 
 image_raw_umount() {
@@ -153,8 +157,10 @@ image_raw_umount() {
 	req=(workdir bootpart rootpart)
 	ckreq || return 1
 
-	sudo umount $workdir/mnt/boot && act "unmounted boot partition" || zerr
-	sleep 1
+	[[ "$parted_type" == gpt ]] || {
+		sudo umount $workdir/mnt/boot && act "unmounted boot partition" || zerr
+		sleep 1
+	}
 	sudo umount $workdir/mnt      && act "unmounted root partition" || zerr
 }