<section xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xml:id="sec-release-15.09">
  <title>Release 15.09 (<quote>Dingo</quote>, 2015/09/30)</title>
  <para>
    In addition to numerous new and upgraded packages, this release has
    the following highlights:
  </para>
  <itemizedlist>
    <listitem>
      <para>
        The <link xlink:href="http://haskell.org/">Haskell</link>
        packages infrastructure has been re-designed from the ground up
        (&quot;Haskell NG&quot;). NixOS now distributes the latest
        version of every single package registered on
        <link xlink:href="http://hackage.haskell.org/">Hackage</link> --
        well in excess of 8,000 Haskell packages. Detailed instructions
        on how to use that infrastructure can be found in the
        <link xlink:href="https://nixos.org/nixpkgs/manual/#users-guide-to-the-haskell-infrastructure">User's
        Guide to the Haskell Infrastructure</link>. Users migrating from
        an earlier release may find helpful information below, in the
        list of backwards-incompatible changes. Furthermore, we
        distribute 51(!) additional Haskell package sets that provide
        every single <link xlink:href="http://www.stackage.org/">LTS
        Haskell</link> release since version 0.0 as well as the most
        recent <link xlink:href="http://www.stackage.org/">Stackage
        Nightly</link> snapshot. The announcement
        <link xlink:href="https://nixos.org/nix-dev/2015-September/018138.html">&quot;Full
        Stackage Support in Nixpkgs&quot;</link> gives additional
        details.
      </para>
    </listitem>
    <listitem>
      <para>
        Nix has been updated to version 1.10, which among other
        improvements enables cryptographic signatures on binary caches
        for improved security.
      </para>
    </listitem>
    <listitem>
      <para>
        You can now keep your NixOS system up to date automatically by
        setting
      </para>
    </listitem>
  </itemizedlist>
  <programlisting language="bash">
{
  system.autoUpgrade.enable = true;
}
</programlisting>
  <para>
    This will cause the system to periodically check for updates in your
    current channel and run <literal>nixos-rebuild</literal>.
  </para>
  <itemizedlist>
    <listitem>
      <para>
        This release is based on Glibc 2.21, GCC 4.9 and Linux 3.18.
      </para>
    </listitem>
    <listitem>
      <para>
        GNOME has been upgraded to 3.16.
      </para>
    </listitem>
    <listitem>
      <para>
        Xfce has been upgraded to 4.12.
      </para>
    </listitem>
    <listitem>
      <para>
        KDE 5 has been upgraded to KDE Frameworks 5.10, Plasma 5.3.2 and
        Applications 15.04.3. KDE 4 has been updated to kdelibs-4.14.10.
      </para>
    </listitem>
    <listitem>
      <para>
        E19 has been upgraded to 0.16.8.15.
      </para>
    </listitem>
  </itemizedlist>
  <para>
    The following new services were added since the last release:
  </para>
  <itemizedlist>
    <listitem>
      <para>
        <literal>services/mail/exim.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/apache-kafka.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/canto-daemon.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/confd.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/devmon.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/gitit.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/ihaskell.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/mbpfan.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/mediatomb.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/mwlib.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/parsoid.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/plex.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/ripple-rest.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/ripple-data-api.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/subsonic.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/misc/sundtek.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/monitoring/cadvisor.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/monitoring/das_watchdog.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/monitoring/grafana.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/monitoring/riemann-tools.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/monitoring/teamviewer.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/network-filesystems/u9fs.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/aiccu.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/asterisk.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/bird.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/charybdis.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/docker-registry-server.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/fan.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/firefox/sync-server.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/gateone.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/heyefi.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/i2p.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/lambdabot.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/mstpd.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/nix-serve.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/nylon.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/racoon.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/skydns.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/shout.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/softether.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/sslh.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/tinc.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/tlsdated.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/tox-bootstrapd.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/tvheadend.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/networking/zerotierone.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/scheduling/marathon.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/security/fprintd.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/security/hologram.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/security/munge.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/system/cloud-init.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/web-servers/shellinabox.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/web-servers/uwsgi.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/x11/unclutter.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>services/x11/display-managers/sddm.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>system/boot/coredump.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>system/boot/loader/loader.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>system/boot/loader/generic-extlinux-compatible</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>system/boot/networkd.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>system/boot/resolved.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>system/boot/timesyncd.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>tasks/filesystems/exfat.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>tasks/filesystems/ntfs.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>tasks/filesystems/vboxsf.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>virtualisation/virtualbox-host.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>virtualisation/vmware-guest.nix</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>virtualisation/xen-dom0.nix</literal>
      </para>
    </listitem>
  </itemizedlist>
  <para>
    When upgrading from a previous release, please be aware of the
    following incompatible changes:
  </para>
  <itemizedlist spacing="compact">
    <listitem>
      <para>
        <literal>sshd</literal> no longer supports DSA and ECDSA host
        keys by default. If you have existing systems with such host
        keys and want to continue to use them, please set
      </para>
    </listitem>
  </itemizedlist>
  <programlisting language="bash">
{
  system.stateVersion = &quot;14.12&quot;;
}
</programlisting>
  <para>
    The new option <literal>system.stateVersion</literal> ensures that
    certain configuration changes that could break existing systems
    (such as the <literal>sshd</literal> host key setting) will maintain
    compatibility with the specified NixOS release. NixOps sets the
    state version of existing deployments automatically.
  </para>
  <itemizedlist>
    <listitem>
      <para>
        <literal>cron</literal> is no longer enabled by default, unless
        you have a non-empty
        <literal>services.cron.systemCronJobs</literal>. To force
        <literal>cron</literal> to be enabled, set
        <literal>services.cron.enable = true</literal>.
      </para>
    </listitem>
    <listitem>
      <para>
        Nix now requires binary caches to be cryptographically signed.
        If you have unsigned binary caches that you want to continue to
        use, you should set
        <literal>nix.requireSignedBinaryCaches = false</literal>.
      </para>
    </listitem>
    <listitem>
      <para>
        Steam now doesn't need root rights to work. Instead of using
        <literal>*-steam-chrootenv</literal>, you should now just run
        <literal>steam</literal>. <literal>steamChrootEnv</literal>
        package was renamed to <literal>steam</literal>, and old
        <literal>steam</literal> package -- to
        <literal>steamOriginal</literal>.
      </para>
    </listitem>
    <listitem>
      <para>
        CMPlayer has been renamed to bomi upstream. Package
        <literal>cmplayer</literal> was accordingly renamed to
        <literal>bomi</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        Atom Shell has been renamed to Electron upstream. Package
        <literal>atom-shell</literal> was accordingly renamed to
        <literal>electron</literal>
      </para>
    </listitem>
    <listitem>
      <para>
        Elm is not released on Hackage anymore. You should now use
        <literal>elmPackages.elm</literal> which contains the latest Elm
        platform.
      </para>
    </listitem>
    <listitem>
      <para>
        The CUPS printing service has been updated to version
        <literal>2.0.2</literal>. Furthermore its systemd service has
        been renamed to <literal>cups.service</literal>.
      </para>
      <para>
        Local printers are no longer shared or advertised by default.
        This behavior can be changed by enabling
        <literal>services.printing.defaultShared</literal> or
        <literal>services.printing.browsing</literal> respectively.
      </para>
    </listitem>
    <listitem>
      <para>
        The VirtualBox host and guest options have been named more
        consistently. They can now found in
        <literal>virtualisation.virtualbox.host.*</literal> instead of
        <literal>services.virtualboxHost.*</literal> and
        <literal>virtualisation.virtualbox.guest.*</literal> instead of
        <literal>services.virtualboxGuest.*</literal>.
      </para>
      <para>
        Also, there now is support for the <literal>vboxsf</literal>
        file system using the <literal>fileSystems</literal>
        configuration attribute. An example of how this can be used in a
        configuration:
      </para>
    </listitem>
  </itemizedlist>
  <programlisting language="bash">
{
  fileSystems.&quot;/shiny&quot; = {
    device = &quot;myshinysharedfolder&quot;;
    fsType = &quot;vboxsf&quot;;
  };
}
</programlisting>
  <itemizedlist spacing="compact">
    <listitem>
      <para>
        &quot;<literal>nix-env -qa</literal>&quot; no longer discovers
        Haskell packages by name. The only packages visible in the
        global scope are <literal>ghc</literal>,
        <literal>cabal-install</literal>, and <literal>stack</literal>,
        but all other packages are hidden. The reason for this
        inconvenience is the sheer size of the Haskell package set.
        Name-based lookups are expensive, and most
        <literal>nix-env -qa</literal> operations would become much
        slower if we'd add the entire Hackage database into the top
        level attribute set. Instead, the list of Haskell packages can
        be displayed by running:
      </para>
    </listitem>
  </itemizedlist>
  <programlisting>
nix-env -f &quot;&lt;nixpkgs&gt;&quot; -qaP -A haskellPackages
</programlisting>
  <para>
    Executable programs written in Haskell can be installed with:
  </para>
  <programlisting>
nix-env -f &quot;&lt;nixpkgs&gt;&quot; -iA haskellPackages.pandoc
</programlisting>
  <para>
    Installing Haskell <emphasis>libraries</emphasis> this way, however,
    is no longer supported. See the next item for more details.
  </para>
  <itemizedlist>
    <listitem>
      <para>
        Previous versions of NixOS came with a feature called
        <literal>ghc-wrapper</literal>, a small script that allowed GHC
        to transparently pick up on libraries installed in the user's
        profile. This feature has been deprecated;
        <literal>ghc-wrapper</literal> was removed from the
        distribution. The proper way to register Haskell libraries with
        the compiler now is the
        <literal>haskellPackages.ghcWithPackages</literal> function. The
        <link xlink:href="https://nixos.org/nixpkgs/manual/#users-guide-to-the-haskell-infrastructure">User's
        Guide to the Haskell Infrastructure</link> provides more
        information about this subject.
      </para>
    </listitem>
    <listitem>
      <para>
        All Haskell builds that have been generated with version 1.x of
        the <literal>cabal2nix</literal> utility are now invalid and
        need to be re-generated with a current version of
        <literal>cabal2nix</literal> to function. The most recent
        version of this tool can be installed by running
        <literal>nix-env -i cabal2nix</literal>.
      </para>
    </listitem>
    <listitem>
      <para>
        The <literal>haskellPackages</literal> set in Nixpkgs used to
        have a function attribute called <literal>extension</literal>
        that users could override in their
        <literal>~/.nixpkgs/config.nix</literal> files to configure
        additional attributes, etc. That function still exists, but it's
        now called <literal>overrides</literal>.
      </para>
    </listitem>
    <listitem>
      <para>
        The OpenBLAS library has been updated to version
        <literal>0.2.14</literal>. Support for the
        <literal>x86_64-darwin</literal> platform was added. Dynamic
        architecture detection was enabled; OpenBLAS now selects
        microarchitecture-optimized routines at runtime, so optimal
        performance is achieved without the need to rebuild OpenBLAS
        locally. OpenBLAS has replaced ATLAS in most packages which use
        an optimized BLAS or LAPACK implementation.
      </para>
    </listitem>
    <listitem>
      <para>
        The <literal>phpfpm</literal> is now using the default PHP
        version (<literal>pkgs.php</literal>) instead of PHP 5.4
        (<literal>pkgs.php54</literal>).
      </para>
    </listitem>
    <listitem>
      <para>
        The <literal>locate</literal> service no longer indexes the Nix
        store by default, preventing packages with potentially numerous
        versions from cluttering the output. Indexing the store can be
        activated by setting
        <literal>services.locate.includeStore = true</literal>.
      </para>
    </listitem>
    <listitem>
      <para>
        The Nix expression search path (<literal>NIX_PATH</literal>) no
        longer contains <literal>/etc/nixos/nixpkgs</literal> by
        default. You can override <literal>NIX_PATH</literal> by setting
        <literal>nix.nixPath</literal>.
      </para>
    </listitem>
    <listitem>
      <para>
        Python 2.6 has been marked as broken (as it no longer receives
        security updates from upstream).
      </para>
    </listitem>
    <listitem>
      <para>
        Any use of module arguments such as <literal>pkgs</literal> to
        access library functions, or to define
        <literal>imports</literal> attributes will now lead to an
        infinite loop at the time of the evaluation.
      </para>
      <para>
        In case of an infinite loop, use the
        <literal>--show-trace</literal> command line argument and read
        the line just above the error message.
      </para>
      <programlisting>
$ nixos-rebuild build --show-trace
…
while evaluating the module argument `pkgs' in &quot;/etc/nixos/my-module.nix&quot;:
infinite recursion encountered
</programlisting>
      <para>
        Any use of <literal>pkgs.lib</literal>, should be replaced by
        <literal>lib</literal>, after adding it as argument of the
        module. The following module
      </para>
      <programlisting language="bash">
{ config, pkgs, ... }:

with pkgs.lib;

{
  options = {
    foo = mkOption { … };
  };
  config = mkIf config.foo { … };
}
</programlisting>
      <para>
        should be modified to look like:
      </para>
      <programlisting language="bash">
{ config, pkgs, lib, ... }:

with lib;

{
  options = {
    foo = mkOption { option declaration };
  };
  config = mkIf config.foo { option definition };
}
</programlisting>
      <para>
        When <literal>pkgs</literal> is used to download other projects
        to import their modules, and only in such cases, it should be
        replaced by <literal>(import &lt;nixpkgs&gt; {})</literal>. The
        following module
      </para>
      <programlisting language="bash">
{ config, pkgs, ... }:

let
  myProject = pkgs.fetchurl {
    src = url;
    sha256 = hash;
  };
in

{
  imports = [ &quot;${myProject}/module.nix&quot; ];
}
</programlisting>
      <para>
        should be modified to look like:
      </para>
      <programlisting language="bash">
{ config, pkgs, ... }:

let
  myProject = (import &lt;nixpkgs&gt; {}).fetchurl {
    src = url;
    sha256 = hash;
  };
in

{
  imports = [ &quot;${myProject}/module.nix&quot; ];
}
</programlisting>
    </listitem>
  </itemizedlist>
  <para>
    Other notable improvements:
  </para>
  <itemizedlist>
    <listitem>
      <para>
        The nixos and nixpkgs channels were unified, so one
        <emphasis>can</emphasis> use
        <literal>nix-env -iA nixos.bash</literal> instead of
        <literal>nix-env -iA nixos.pkgs.bash</literal>. See
        <link xlink:href="https://github.com/NixOS/nixpkgs/commit/2cd7c1f198">the
        commit</link> for details.
      </para>
    </listitem>
    <listitem>
      <para>
        Users running an SSH server who worry about the quality of their
        <literal>/etc/ssh/moduli</literal> file with respect to the
        <link xlink:href="https://stribika.github.io/2015/01/04/secure-secure-shell.html">vulnerabilities
        discovered in the Diffie-Hellman key exchange</link> can now
        replace OpenSSH's default version with one they generated
        themselves using the new
        <literal>services.openssh.moduliFile</literal> option.
      </para>
    </listitem>
    <listitem>
      <para>
        A newly packaged TeX Live 2015 is provided in
        <literal>pkgs.texlive</literal>, split into 6500 nix packages.
        For basic user documentation see
        <link xlink:href="https://github.com/NixOS/nixpkgs/blob/release-15.09/pkgs/tools/typesetting/tex/texlive/default.nix#L1">the
        source</link>. Beware of
        <link xlink:href="https://github.com/NixOS/nixpkgs/issues/9757">an
        issue</link> when installing a too large package set. The plan
        is to deprecate and maybe delete the original TeX packages until
        the next release.
      </para>
    </listitem>
    <listitem>
      <para>
        <literal>buildEnv.env</literal> on all Python interpreters is
        now available for nix-shell interoperability.
      </para>
    </listitem>
  </itemizedlist>
</section>
