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diff --git a/nixos/doc/manual/configuration/abstractions.xml b/nixos/doc/manual/configuration/abstractions.xml
deleted file mode 100644
index df9ff2615e1..00000000000
--- a/nixos/doc/manual/configuration/abstractions.xml
+++ /dev/null
@@ -1,101 +0,0 @@
-<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-module-abstractions">
- <title>Abstractions</title>
-
- <para>
-  If you find yourself repeating yourself over and over, it’s time to
-  abstract. Take, for instance, this Apache HTTP Server configuration:
-<programlisting>
-{
-  <xref linkend="opt-services.httpd.virtualHosts"/> =
-    { "blog.example.org" = {
-        documentRoot = "/webroot/blog.example.org";
-        adminAddr = "alice@example.org";
-        forceSSL = true;
-        enableACME = true;
-        enablePHP = true;
-      };
-      "wiki.example.org" = {
-        documentRoot = "/webroot/wiki.example.org";
-        adminAddr = "alice@example.org";
-        forceSSL = true;
-        enableACME = true;
-        enablePHP = true;
-      };
-    };
-}
-</programlisting>
-  It defines two virtual hosts with nearly identical configuration; the only
-  difference is the document root directories. To prevent this
-  duplication, we can use a <literal>let</literal>:
-<programlisting>
-let
-  commonConfig =
-    { adminAddr = "alice@example.org";
-      forceSSL = true;
-      enableACME = true;
-    };
-in
-{
-  <xref linkend="opt-services.httpd.virtualHosts"/> =
-    { "blog.example.org" = (commonConfig // { documentRoot = "/webroot/blog.example.org"; });
-      "wiki.example.org" = (commonConfig // { documentRoot = "/webroot/wiki.example.com"; });
-    };
-}
-</programlisting>
-  The <literal>let commonConfig = <replaceable>...</replaceable></literal>
-  defines a variable named <literal>commonConfig</literal>. The
-  <literal>//</literal> operator merges two attribute sets, so the
-  configuration of the second virtual host is the set
-  <literal>commonConfig</literal> extended with the document root option.
- </para>
-
- <para>
-  You can write a <literal>let</literal> wherever an expression is allowed.
-  Thus, you also could have written:
-<programlisting>
-{
-  <xref linkend="opt-services.httpd.virtualHosts"/> =
-    let commonConfig = <replaceable>...</replaceable>; in
-    { "blog.example.org" = (commonConfig // { <replaceable>...</replaceable> })
-      "wiki.example.org" = (commonConfig // { <replaceable>...</replaceable> })
-    };
-}
-</programlisting>
-  but not <literal>{ let commonConfig = <replaceable>...</replaceable>; in
-  <replaceable>...</replaceable>; }</literal> since attributes (as opposed to
-  attribute values) are not expressions.
- </para>
-
- <para>
-  <emphasis>Functions</emphasis> provide another method of abstraction. For
-  instance, suppose that we want to generate lots of different virtual hosts,
-  all with identical configuration except for the document root. This can be done
-  as follows:
-<programlisting>
-{
-  <xref linkend="opt-services.httpd.virtualHosts"/> =
-    let
-      makeVirtualHost = webroot:
-        { documentRoot = webroot;
-          adminAddr = "alice@example.org";
-          forceSSL = true;
-          enableACME = true;
-        };
-    in
-      { "example.org" = (makeVirtualHost "/webroot/example.org");
-        "example.com" = (makeVirtualHost "/webroot/example.com");
-        "example.gov" = (makeVirtualHost "/webroot/example.gov");
-        "example.nl" = (makeVirtualHost "/webroot/example.nl");
-      };
-}
-</programlisting>
-  Here, <varname>makeVirtualHost</varname> is a function that takes a single
-  argument <literal>webroot</literal> and returns the configuration for a virtual
-  host. That function is then called for several names to produce the list of
-  virtual host configurations.
- </para>
-</section>