diff --git a/en/appendices/5-1-upgrade-guide.rst b/en/appendices/5-1-upgrade-guide.rst
index 34a8216798..1287cb0833 100644
--- a/en/appendices/5-1-upgrade-guide.rst
+++ b/en/appendices/5-1-upgrade-guide.rst
@@ -40,6 +40,10 @@ Http
 - ``Client`` now emits ``HttpClient.beforeSend`` and ``HttpClient.afterSend``
   events when requests are sent. You can use these events to perform logging,
   caching or collect telemetry.
+- ``Http\Server::terminate()`` was added. This method triggers the
+  ``Server.terminate`` event which can be used to run logic after the response
+  has been sent in fastcgi environments. In other environments the
+  ``Server.terminate`` event runs *before* the response has been sent.
 
 TestSuite
 ---------
diff --git a/en/controllers/request-response.rst b/en/controllers/request-response.rst
index 47f1c5671c..af4866dde0 100644
--- a/en/controllers/request-response.rst
+++ b/en/controllers/request-response.rst
@@ -1040,7 +1040,7 @@ will make the browser remove its local cookie::
 .. _cors-headers:
 
 Setting Cross Origin Request Headers (CORS)
-===========================================
+-------------------------------------------
 
 The ``cors()`` method is used to define `HTTP Access Control
 <https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS>`__
@@ -1067,6 +1067,27 @@ criteria are met:
     is very application specific. We recommend you build your own ``CORSMiddleware``
     if you need one and adjust the response object as desired.
 
+Running logic after the Response has been sent
+----------------------------------------------
+
+In fastcgi based environments you can listen to the ``Server.terminate`` event
+to run logic **after** the response has been sent to the client. Make sure your
+application's **webroot/index.php** contains the following::
+
+    $app = new Application(dirname(__DIR__) . '/config'))
+    $server = new Server($app);
+
+    $response = $server->run(ServerRequest::fromGlobals());
+    $server->emit($response);
+    $request = $app->getContainer()->get(ServerRequest::class);
+    $server->terminate($request, $response);
+
+.. warning::
+   In non fastcgi environments the ``Server.terminate`` event is fired before
+   the response is sent.
+
+.. versionadded:: 5.1.0
+
 Common Mistakes with Immutable Responses
 ========================================