+Plugins can be used to add additional features to ikiwiki. The interface
+is quite flexible, allowing plugins to implement additional markup
+languages, register [[PreProcessorDirective]]s, hook into [[CGI]] mode,
+and more. Most of ikiwiki's features are actually provided by plugins.
+Ikiwiki's backend RCS support is also pluggable, so support for new
+revision control systems can be added to ikiwiki.