If you are installing a package by hand and wants to revert back to the previous state, best is to :
- when you ./configure it, use the various --prefix directives (do a ./configure --help for information on that) - when you want to remove, make uninstall in the source dir (so don't remove it!) - if it does not have a remove, usually if you install it inside /home/${username}/whatever, then removing that is fine. Best thing though is to write an ebuild and then Portage will sandbox the build so it knows every file that has been installed. The package knows where to link to when it goes into the ./configure stage and won't act like windows, installing stuffs into registry or the like ... everything's nicely contained inside /lib and /share folders (except /etc files ...which you can safely ignore them there - those are just text files and you'll know where they are anyway if you intend to configure miro)