diff --git a/debian/changelog b/debian/changelog
index b8ab2608..75035e23 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,12 @@
+livecd-rootfs (2.236) UNRELEASED; urgency=medium
+
+  [ James Hunt ]
+  * ubuntu-core:
+    - Perform in-place edit.
+    - Allow variable expansion.
+
+ -- Colin Watson <cjwatson@ubuntu.com>  Tue, 05 Aug 2014 10:41:04 +0200
+
 livecd-rootfs (2.235) utopic; urgency=medium
 
   * Only add the ubuntu-core hooks for the system-image subproject.
diff --git a/live-build/ubuntu-core/hooks/03-boot_with_systemd.chroot b/live-build/ubuntu-core/hooks/03-boot_with_systemd.chroot
index d8f4c7db..563af73e 100755
--- a/live-build/ubuntu-core/hooks/03-boot_with_systemd.chroot
+++ b/live-build/ubuntu-core/hooks/03-boot_with_systemd.chroot
@@ -3,7 +3,7 @@
 # Boot using systemd and disable quiet boot
 # to see what is happening.
 systemd=/lib/systemd/systemd
-sed \
-    -e 's,^\([ 	]*GRUB_CMDLINE_LINUX\)=""$,\1="init=$systemd",g' \
+sed -i \
+    -e "s,^\\([ 	]*GRUB_CMDLINE_LINUX\\)=\"\"$,\\1=\"init=$systemd\",g" \
     -e 's,^\([ 	]*GRUB_CMDLINE_LINUX_DEFAULT\)="quiet splash",\1="",g' \
     /etc/default/grub