<chapter 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-releases">
 <title>Releases</title>
 <section xml:id="release-process">
  <title>Release process</title>

  <para>
   Going through an example of releasing NixOS 19.09:
  </para>

  <section xml:id="one-month-before-the-beta">
   <title>One month before the beta</title>

   <itemizedlist>
    <listitem>
     <para>
      Create an announcement on <link xlink:href="https://discourse.nixos.org">Discourse</link> as a warning about upcoming beta <quote>feature freeze</quote> in a month. <link xlink:href="https://discourse.nixos.org/t/nixos-19-09-feature-freeze/3707">See this post as an example</link>.
     </para>
    </listitem>
    <listitem>
     <para>
      Discuss with Eelco Dolstra and the community (via IRC, ML) about what will reach the deadline. Any issue or Pull Request targeting the release should be included in the release milestone.
     </para>
    </listitem>
    <listitem>
     <para>
      Remove attributes that we know we will not be able to support, especially if there is a stable alternative. E.g. Check that our Linux kernels’ <link xlink:href="https://www.kernel.org/category/releases.html">projected end-of-life</link> are after our release projected end-of-life.
     </para>
    </listitem>
   </itemizedlist>
  </section>

  <section xml:id="at-beta-release-time">
   <title>At beta release time</title>

   <orderedlist>
    <listitem>
     <para>
      From the master branch run:
     </para>
<programlisting>
git checkout -b release-19.09
</programlisting>
    </listitem>
    <listitem>
     <para>
      <link xlink:href="https://github.com/NixOS/nixpkgs/commit/10e61bf5be57736035ec7a804cb0bf3d083bf2cf#diff-9c798092bac0caeb5c52d509be0ca263R69">Bump the <literal>system.defaultChannel</literal> attribute in <literal>nixos/modules/misc/version.nix</literal></link>
     </para>
    </listitem>
    <listitem>
     <para>
      <link xlink:href="https://github.com/NixOS/nixpkgs/commit/10e61bf5be57736035ec7a804cb0bf3d083bf2cf#diff-831e8d9748240fb23e6734fdc2a6d16eR15">Update <literal>versionSuffix</literal> in <literal>nixos/release.nix</literal></link>
     </para>
    </listitem>
   </orderedlist>

   <para>
    To get the commit count, use the following command:
   </para>

<programlisting>
git rev-list --count release-19.09
</programlisting>

   <orderedlist>
    <listitem>
     <para>
      Edit changelog at <literal>nixos/doc/manual/release-notes/rl-1909.xml</literal>.
     </para>
     <itemizedlist>
      <listitem>
       <para>
        Get all new NixOS modules:
       </para>
<programlisting>
git diff release-19.03..release-19.09 nixos/modules/module-list.nix | grep ^+
</programlisting>
      </listitem>
      <listitem>
       <para>
        Note systemd, kernel, glibc, desktop environment, and Nix upgrades.
       </para>
      </listitem>
     </itemizedlist>
    </listitem>
    <listitem>
     <para>
      Tag the release:
     </para>
<programlisting>
git tag --annotate --message="Release 19.09-beta" 19.09-beta
git push upstream 19.09-beta
</programlisting>
    </listitem>
    <listitem>
     <para>
      <link xlink:href="https://github.com/NixOS/nixpkgs/commit/01268fda85b7eee4e462c873d8654f975067731f#diff-2bc0e46110b507d6d5a344264ef15adaR1">On the <literal>master</literal> branch, increment the <literal>.version</literal> file</link>
     </para>
<programlisting>
echo -n "20.03" > .version
</programlisting>
    </listitem>
    <listitem>
     <para>
      <link xlink:href="https://github.com/NixOS/nixpkgs/commit/01268fda85b7eee4e462c873d8654f975067731f#diff-03f3d41b68f62079c55001f1a1c55c1dR137">Update <literal>codeName</literal> in <literal>lib/trivial.nix</literal></link> This will be the name for the next release.
     </para>
    </listitem>
    <listitem>
     <para>
      <link xlink:href="https://github.com/NixOS/nixpkgs/commit/01268fda85b7eee4e462c873d8654f975067731f#diff-e7ee5ff686cdcc513ca089d6e5682587R11">Create a new release notes file for the upcoming release + 1</link>, in our case this is <literal>rl-2003.xml</literal>.
     </para>
    </listitem>
    <listitem>
     <para>
      Contact the infrastructure team to create the necessary Hydra Jobsets.
     </para>
    </listitem>
    <listitem>
     <para>
      <link xlink:href="https://github.com/NixOS/nixos-org-configurations/blob/master/channels.nix">Create a channel at https://nixos.org/channels by creating a PR to nixos-org-configurations, changing <literal>channels.nix</literal></link>
     </para>
    </listitem>
    <listitem>
     <para>
      Get all Hydra jobsets for the release to have their first evaluation.
     </para>
    </listitem>
    <listitem>
     <para>
      <link xlink:href="https://github.com/NixOS/nixpkgs/issues/13559">Create an issue for tracking Zero Hydra Failures progress. ZHF is an effort to get build failures down to zero.</link>
     </para>
    </listitem>
   </orderedlist>
  </section>

  <section xml:id="during-beta">
   <title>During Beta</title>

   <itemizedlist>
    <listitem>
     <para>
      Monitor the master branch for bugfixes and minor updates and cherry-pick them to the release branch.
     </para>
    </listitem>
   </itemizedlist>
  </section>

  <section xml:id="before-the-final-release">
   <title>Before the final release</title>

   <itemizedlist>
    <listitem>
     <para>
      Re-check that the release notes are complete.
     </para>
    </listitem>
    <listitem>
     <para>
      Release Nix (currently only Eelco Dolstra can do that). <link xlink:href="https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/installer/tools/nix-fallback-paths.nix">Make sure fallback is updated.</link>
     </para>
    </listitem>
    <listitem>
     <para>
      <link xlink:href="https://github.com/NixOS/nixpkgs/commit/40fd9ae3ac8048758abdcfc7d28a78b5f22fe97e">Update README.md with new stable NixOS version information.</link>
     </para>
    </listitem>
    <listitem>
     <para>
      Change <literal>stableBranch</literal> to <literal>true</literal> in Hydra and wait for the channel to update.
     </para>
    </listitem>
   </itemizedlist>
  </section>

  <section xml:id="at-final-release-time">
   <title>At final release time</title>

   <orderedlist>
    <listitem>
     <para>
      Update <xref linkend="sec-upgrading" /> section of the manual to match new stable release version.
     </para>
    </listitem>
    <listitem>
     <para>
      Update <literal>rl-1909.xml</literal> with the release date.
     </para>
    </listitem>
    <listitem>
     <para>
      Tag the final release
     </para>
<programlisting>
git tag --annotate --message="Release 19.09" 19.09
git push upstream 19.09
</programlisting>
    </listitem>
    <listitem>
     <para>
      Update <link xlink:href="https://github.com/NixOS/nixos-homepage">nixos-homepage</link> for the release.
     </para>
     <orderedlist>
      <listitem>
       <para>
        <link xlink:href="https://github.com/NixOS/nixos-homepage/blob/47ac3571c4d71e841fd4e6c6e1872e762b9c4942/Makefile#L1">Update <literal>NIXOS_SERIES</literal> in the <literal>Makefile</literal></link>.
       </para>
      </listitem>
      <listitem>
       <para>
        <link xlink:href="https://github.com/NixOS/nixos-homepage/blob/47ac3571c4d71e841fd4e6c6e1872e762b9c4942/nixos-release.tt#L1">Update <literal>nixos-release.tt</literal> with the new NixOS version</link>.
       </para>
      </listitem>
      <listitem>
       <para>
        <link xlink:href="https://github.com/NixOS/nixos-homepage/blob/47ac3571c4d71e841fd4e6c6e1872e762b9c4942/flake.nix#L10">Update the <literal>flake.nix</literal> input <literal>released-nixpkgs</literal> to 19.09</link>.
       </para>
      </listitem>
      <listitem>
       <para>
        Run <literal>./update.sh</literal> (this updates flake.lock to updated channel).
       </para>
      </listitem>
      <listitem>
       <para>
        <link xlink:href="https://github.com/NixOS/nixos-homepage/blob/a5626c71c03a2dd69086564e56f1a230a2bb177a/logo/nixos-logo-19.09-loris-lores.png">Add a compressed version of the NixOS logo for 19.09</link>.
       </para>
      </listitem>
      <listitem>
       <para>
        <link xlink:href="https://github.com/NixOS/nixos-homepage/commit/a5626c71c03a2dd69086564e56f1a230a2bb177a#diff-9cdc6434d3e4fd93a6e5bb0a531a7c71R5">Compose a news item for the website RSS feed</link>.
       </para>
      </listitem>
     </orderedlist>
    </listitem>
    <listitem>
     <para>
      Create a new topic on <link xlink:href="https://discourse.nixos.org/">the Discourse instance</link> to announce the release.
     </para>
    </listitem>
   </orderedlist>

   <para>
    You should include the following information:
   </para>

   <itemizedlist>
    <listitem>
     <para>
      Number of commits for the release:
     </para>
<programlisting>
bash git log release-19.03..release-19.09 --format=%an | wc -l
</programlisting>
    </listitem>
    <listitem>
     <para>
      Commits by contributor:
     </para>
<programlisting>
git shortlog --summary --numbered release-19.03..release-19.09
</programlisting>
    </listitem>
   </itemizedlist>

   <para>
    Best to check how the previous post was formulated to see what needs to be included.
   </para>
  </section>
 </section>
 <section xml:id="release-management-team">
  <title>Release Management Team</title>

  <para>
   For each release there are two release managers. After each release the release manager having managed two releases steps down and the release management team of the last release appoints a new release manager.
  </para>

  <para>
   This makes sure a release management team always consists of one release manager who already has managed one release and one release manager being introduced to their role, making it easier to pass on knowledge and experience.
  </para>

  <para>
   Release managers for the current NixOS release are tracked by GitHub team <link xlink:href="https://github.com/orgs/NixOS/teams/nixos-release-managers/members"><literal>@NixOS/nixos-release-managers</literal></link>.
  </para>

  <para>
   A release manager’s role and responsibilities are:
  </para>

  <itemizedlist>
   <listitem>
    <para>
     manage the release process
    </para>
   </listitem>
   <listitem>
    <para>
     start discussions about features and changes for a given release
    </para>
   </listitem>
   <listitem>
    <para>
     create a roadmap
    </para>
   </listitem>
   <listitem>
    <para>
     release in cooperation with Eelco Dolstra
    </para>
   </listitem>
   <listitem>
    <para>
     decide which bug fixes, features, etc… get backported after a release
    </para>
   </listitem>
  </itemizedlist>
 </section>
 <section xml:id="release-schedule">
  <title>Release schedule</title>

  <informaltable>
   <tgroup cols="2">
    <colspec align="left" />
    <colspec align="left" />
    <thead>
     <row>
      <entry>
            Date
          </entry>
      <entry>
            Event
          </entry>
     </row>
    </thead>
    <tbody>
     <row>
      <entry>
            2016-07-25
          </entry>
      <entry>
            Send email to nix-dev about upcoming branch-off
          </entry>
     </row>
     <row>
      <entry>
            2016-09-01
          </entry>
      <entry><literal>release-16.09</literal> branch and corresponding jobsets are created,
            change freeze
          </entry>
     </row>
     <row>
      <entry>
            2016-09-30
          </entry>
      <entry>
            NixOS 16.09 released
          </entry>
     </row>
    </tbody>
   </tgroup>
  </informaltable>
 </section>
</chapter>
