Nix Release 0.7 Features

doc/manual/source/release-notes/rl-0.7.md

fe2a5dc601afc18b2cb3c97b6875ac2d6d0cfc85714371ab00000003000003fd

# Release 0.7 (2005-01-12)

  - 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 *sequence* of patches
    to an installed component, Nix will use it. Patches are currently
    generated automatically between Nixpkgs (pre-)releases.

  - Simplifications to the substitute mechanism.

  - Nix-pull now stores downloaded manifests in
    `/nix/var/nix/manifests`.

  - 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.

Chunks

f7132231 (1st chunk of `doc/manual/source/release-notes/rl-0.7.md`)

Title: Nix Release 0.7 Features

Summary

Nix Release 0.7 introduces several key enhancements, including binary patching for more efficient component upgrades, allowing for incremental updates rather than full downloads. The update also simplifies the substitute mechanism, changes the storage location for `nix-pull` manifests, and standardizes file metadata in the Nix store after builds to ensure consistency and reveal timestamp dependencies.