nixpkgs/nixos/doc/manual/installation/obtaining.xml

<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="sec-obtaining">
 <title>Obtaining NixOS</title>
 <para>
  NixOS ISO images can be downloaded from the
  <link
xlink:href="https://nixos.org/nixos/download.html">NixOS download
  page</link>. There are a number of installation options. If you happen to
  have an optical drive and a spare CD, burning the image to CD and booting
  from that is probably the easiest option. Most people will need to prepare a
  USB stick to boot from. <xref linkend="sec-booting-from-usb"/> describes the
  preferred method to prepare a USB stick. A number of alternative methods are
  presented in the
  <link
xlink:href="https://nixos.wiki/wiki/NixOS_Installation_Guide#Making_the_installation_media">NixOS
  Wiki</link>.
 </para>
 <para>
  As an alternative to installing NixOS yourself, you can get a running NixOS
  system through several other means:
  <itemizedlist>
   <listitem>
    <para>
     Using virtual appliances in Open Virtualization Format (OVF) that can be
     imported into VirtualBox. These are available from the
     <link xlink:href="https://nixos.org/nixos/download.html">NixOS download
     page</link>.
    </para>
   </listitem>
   <listitem>
    <para>
     Using AMIs for Amazon’s EC2. To find one for your region and instance
     type, please refer to the
     <link
    xlink:href="https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/virtualisation/ec2-amis.nix">list
     of most recent AMIs</link>.
    </para>
   </listitem>
   <listitem>
    <para>
     Using NixOps, the NixOS-based cloud deployment tool, which allows you to
     provision VirtualBox and EC2 NixOS instances from declarative
     specifications. Check out the
     <link
    xlink:href="https://nixos.org/nixops">NixOps homepage</link> for
     details.
    </para>
   </listitem>
  </itemizedlist>
 </para>
</chapter>