diff --git a/appcast.html b/appcast.html
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+---
+layout: default
+id: appcast
+title: Appcast
+---
+<div class="container">
+  <div class="row">
+    <div class="col-md-12">
+      <h2>XML namespace</h2>
+      <p>Sparkle's <abbr>XML</abbr> namespace is <code>http://www.andymatuschak.org/xml-namespaces/sparkle</code>. It is an identifier. It is not a webpage. Please don't pay attention to what is hosted there. <abbr>XML</abbr> namespaces were a bad idea.</p>
+      <h2>Appcasts</h2>
+      <p>Information about appcasts is in <a href="/documentation/">the documentation</a>.</p>
+    </div>
+  </div>
+  <hr/>
+</div>