nixpkgs/nixos/doc/manual/development/testing-installer.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="ch-testing-installer">
 <title>Testing the Installer</title>
 <para>
  Building, burning, and booting from an installation CD is rather tedious, so
  here is a quick way to see if the installer works properly:
<screen>
<prompt># </prompt>mount -t tmpfs none /mnt
<prompt># </prompt>nixos-generate-config --root /mnt
<prompt>$ </prompt>nix-build '&lt;nixpkgs/nixos>' -A config.system.build.nixos-install
<prompt># </prompt>./result/bin/nixos-install</screen>
  To start a login shell in the new NixOS installation in
  <filename>/mnt</filename>:
<screen>
<prompt>$ </prompt>nix-build '&lt;nixpkgs/nixos>' -A config.system.build.nixos-enter
<prompt># </prompt>./result/bin/nixos-enter
</screen>
 </para>
</chapter>