A method and system may include capturing a computer system in a file-based manner that promotes single-instancing of files and thus prevents the occurrence of duplicate files, separating the captured computer system into primary file resources and ancillary file resources, and creating a parent image and a child image that refers to the parent image. The method and system may further include writing the primary file resources on the parent image, and writing the ancillary file resources onto the child image. The child image may include a resource-only file and a metadata-only file which provides instructions on how to recreate the file resources stored in the parent image and the child image.