<refentry xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xi="http://www.w3.org/2001/XInclude"> <refmeta> <refentrytitle><filename>configuration.nix</filename></refentrytitle> <manvolnum>5</manvolnum> <refmiscinfo class="source">NixOS</refmiscinfo> <!-- <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> --> </refmeta> <refnamediv> <refname><filename>configuration.nix</filename></refname> <refpurpose>NixOS system configuration specification</refpurpose> </refnamediv> <refsection><title>Description</title> <para>The file <filename>/etc/nixos/configuration.nix</filename> contains the declarative specification of your NixOS system configuration. The command <command>nixos-rebuild</command> takes this file and realises the system configuration specified therein.</para> </refsection> <refsection><title>Options</title> <para>You can use the following options in <filename>configuration.nix</filename>.</para> <xi:include href="options-db.xml" /> </refsection> </refentry>