escaped curly brackets

roles/arch-boxes/templates/arch-boxes.service.j2

@@ -3,6 +3,8 @@ Description=arch-boxes service for deploying images and vagrant boxes
 
 [Service]
 Type=oneshot
+{% raw %}
 ExecStart=/usr/bin/packer-io build -parallel=false -var 'headless=true' -var 'iso_checksum_type=none' -var 'iso_url=file:///srv/ftp/iso/latest/archlinux-{{isotime \"2006.01\"}}.01-x86_64.iso' -except=vmware-iso vagrant.json
+{% endraw %}
 User={{ archboxes_user }}
 WorkingDirectory={{ archboxes_dir }}/arch-boxes