Like the "Kickstart default" provisioning template with its custom pre/packages/post snippets, I'd like to be able to add custom early/late steps do Finish templates. This is valuable when using image-based provisioning if one wants to e.g. install custom packages to the provisioned host before considering provisioning complete or add entries to the host's /etc/hosts file before the bulk of the Finish template completes.

The way I propose this be implemented is with the same approach used in "Kickstart default": snippet_if_exists(template_name + " custom early") as one of the first steps in the template and snippet_if_exists(template_name + " custom late") as one of the last steps.

I'll be sending a PR for this shortly.