Currently the order of the packages install affects the resulting passwd/group files. As the files are installed adduser/addgroup is called and for uid/gid that are not statically defined -- dynamic items are added. Two installations may result in different non-deterministic behavior. We would like a way to generate a system with deterministic uid/gid behavior, while still allows the passwd/group file to be dynamically generated based on the content of the image.
I'm working on an implementation of this feature.
Implemented in commits: 18c99dac52b746b88cd084eb4c2a2ef0329a6ff3 f35bbba65e3e41f8dea1f9ff872d3a9fbd84bf6d