nixpkgs/nixos/doc/manual/release-notes/rl-unstable.xml

<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="sec-release-unstable">

<title>Unstable</title>

<para>In addition to numerous new and upgraded packages, this release
has the following highlights:</para>

<itemizedlist>

  <listitem>
    <para>You can now pin a specific version of NixOS in your <filename>configuration.nix</filename>
    by setting:

<programlisting>
nixos.path = ./nixpkgs-unstable-2015-12-06/nixos;
</programlisting>

    This will make NixOS re-evaluate your configuration with the modules of
    the specified NixOS version at the given path.  For more details, see
    <xref linkend="module-misc-nixos" /></para>
  </listitem>

</itemizedlist>

<para>The following new services were added since the last release:

  <itemizedlist>
    <listitem><para><literal>services/monitoring/longview.nix</literal></para></listitem>
  </itemizedlist>
</para>

<para>When upgrading from a previous release, please be aware of the
following incompatible changes:</para>

<itemizedlist>
  <listitem>
    <para><command>wmiiSnap</command> has been replaced with
    <command>wmii_hg</command>, but
    <command>services.xserver.windowManager.wmii.enable</command> has
    been updated respectively so this only affects you if you have
    explicitly installed <command>wmiiSnap</command>.
    </para>
  </listitem>

  <listitem>
    <para><command>wmiimenu</command> is removed, as it has been
    removed by the developers upstream. Use <command>wimenu</command>
    from the <command>wmii-hg</command> package.</para>
  </listitem>

  <listitem>
    <para>Gitit is no longer automatically added to the module list in
    NixOS and as such there will not be any manual entries for it. You
    will need to add an import statement to your NixOS configuration
    in order to use it, e.g.

<programlisting><![CDATA[
{
  imports = [ <nixos/modules/services/misc/gitit.nix> ];
}
]]></programlisting>

    will include the Gitit service configuration options.</para>
  </listitem>

  <listitem>
    <para><command>nginx</command> does not accept flags for enabling and
    disabling modules anymore. Instead it accepts <literal>modules</literal>
    argument, which is a list of modules to be built in. All modules now
    reside in <literal>nginxModules</literal> set. Example configuration:

<programlisting><![CDATA[
nginx.override {
  modules = [ nginxModules.rtmp nginxModules.dav nginxModules.moreheaders ];
}
]]></programlisting>
    </para>
  </listitem>

  <listitem>
    <para><command>s3sync</command> is removed, as it hasn't been
    developed by upstream for 4 years and only runs with ruby 1.8.
    For an actively-developer alternative look at
    <command>tarsnap</command> and others.
    </para>
  </listitem>

  <listitem>
    <para><command>ruby_1_8</command> has been removed as it's not
    supported from upstream anymore and probably contains security
    issues.
    </para>
  </listitem>

</itemizedlist>

</section>