diff --git a/nixos/doc/manual/release-notes/rl-2009.xml b/nixos/doc/manual/release-notes/rl-2009.xml
index 97b94c5756a7..8d6bcccb9dae 100644
--- a/nixos/doc/manual/release-notes/rl-2009.xml
+++ b/nixos/doc/manual/release-notes/rl-2009.xml
@@ -525,6 +525,14 @@ systemd.services.nginx.serviceConfig.ReadWritePaths = [ "/var/www" ];
      automatically if <literal>stateVersion</literal> is 20.09 or higher.
     </para>
    </listitem>
+   <listitem>
+    <para>
+      <literal>udpt</literal> experienced a complete rewrite from C++ to rust. The configuration format changed from ini to toml.
+      The new configuration documentation can be found at
+      <link xlink:href="https://naim94a.github.io/udpt/config.html">the official website</link> and example
+      configuration is packaged in <literal>${udpt}/share/udpt/udpt.toml</literal>.
+    </para>
+   </listitem>
    <listitem>
     <para>
      We now have a unified <xref linkend="opt-services.xserver.displayManager.autoLogin"/> option interface