I have read a bit about custom cloud image creation for OpenStack. However, I have some questions which relate more to automation of applications in a cloud image. Are there limitations in the number or types of packages that can be installed in an image. For example a want a custom image with several packages from both official ubuntu repos and some private repos, can I install these packages in the image ? My thinking is that if these package are required for all instances that will be created from the image, using post-creation approaches like cloud init or heat isn't apt. Am I right or there are some standards/ limitations.