I didn’t say “personal package manager”. Do you refer to the part “basically my own AUR package”? pacman, the package manager of Archlinux that is also used in EndeavourOS, allows for building custom packages. These custom packages can be installed on your system, which is then seen like a normal package and handled this way with all the defined dependencies and information about the package. You can install the package from a local location, it does not need to be online repository.

Then you can upload it to the AUR, which is exactly that: Arch User Repository. But you don’t have to upload it. Either way such a custom build package is what I referred to my own AUR package. For more information see: https://wiki.archlinux.org/title/Arch_User_Repository