On (11/21/11 12:17), Bernardo Barros wrote: -~> dpkg-reconfigure ? No.. it's not that at all. -~> -~> In fact pacman already have some of those ideas, -~> it tries to be safe when it keeps old package in /var/cache/pacman/pkg, -~> but Nix goes further and tries to make sense of all those changes in the system. -~> -~> I just see some other ideas that could be inspiring futures versions -~> of pacman, that all: -~> -~> http://www.st.ewi.tudelft.nl/~dolstra/pubs/eupfcdm-cbse2005-final.pdf Well, it deals with configuration problems after an update... The point of this paper is basically to automatically test the updated software version in a VM. The only new concept here is "automatically", perhaps. I can't imagine anyone who would do a major server/kernel upgrade w/o trying it in a testbox beforehand. Updates are supposed to be dangerous, that is exactly why we have SLES/RHEL/Debian with lots of backports. For example, you update subversion to a newer version, which has some incompatibility with older DBs. All the NixOS tests will be fine, but suddenly half of your clients can't checkout. If the system is important, I wouldn't rely some dumb software and do all tests myself. -- Leonid Isaev GnuPG key ID: 164B5A6D Key fingerprint: C0DF 20D0 C075 C3F1 E1BE 775A A7AE F6CB 164B 5A6D