<section xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xi="http://www.w3.org/2001/XInclude" version="5.0" xml:id="ch-relnotes-0.7"> <title>Release 0.7 (January 12, 2005)</title> <itemizedlist> <listitem><para>Binary patching. When upgrading components using pre-built binaries (through nix-pull / nix-channel), Nix can automatically download and apply binary patches to already installed components instead of full downloads. Patching is “smart”: if there is a <emphasis>sequence</emphasis> of patches to an installed component, Nix will use it. Patches are currently generated automatically between Nixpkgs (pre-)releases.</para></listitem> <listitem><para>Simplifications to the substitute mechanism.</para></listitem> <listitem><para>Nix-pull now stores downloaded manifests in <filename>/nix/var/nix/manifests</filename>.</para></listitem> <listitem><para>Metadata on files in the Nix store is canonicalised after builds: the last-modified timestamp is set to 0 (00:00:00 1/1/1970), the mode is set to 0444 or 0555 (readable and possibly executable by all; setuid/setgid bits are dropped), and the group is set to the default. This ensures that the result of a build and an installation through a substitute is the same; and that timestamp dependencies are revealed.</para></listitem> </itemizedlist> </section>