diff --git a/desktop_postinstall.sh b/desktop_postinstall.sh
index cce15b1..e8ba019 100644
--- a/desktop_postinstall.sh
+++ b/desktop_postinstall.sh
@@ -15,7 +15,7 @@
 
 # Make sure secureboot is in setup mode before running this
 
-set -e
+set -eu
 
 # Secure boot enrollment
 sudo sbctl enroll-keys
diff --git a/install.sh b/install.sh
index 1b7eab5..5167f1f 100644
--- a/install.sh
+++ b/install.sh
@@ -14,6 +14,8 @@
 # License for the specific language governing permissions and limitations under
 # the License.
 
+set -u
+
 output(){
     printf '\e[1;34m%-6s\e[m\n' "${@}"
 }
diff --git a/update_grub.sh b/update_grub.sh
index d87d1c6..fd2b4d9 100644
--- a/update_grub.sh
+++ b/update_grub.sh
@@ -13,7 +13,7 @@
 # License for the specific language governing permissions and limitations under
 # the License.
 
-set -e
+set -eu
 
 # Install new grub version
 sudo grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=GRUB --disable-shim-lock