+Ikiwiki requires [[MarkDown]] and the `HTML::Parser` perl module be
+installed, and also uses the following perl modules if available:
+`CGI::Session` `CGI::FormBuilder` (version 3.02.02 or newer)
+`HTML::Template` `Mail::Sendmail` `Time::Duration` `Date::Parse`,
+`HTML::Scrubber`, `RPC::XML`, `XML::Simple`, `XML::Feed`.
+
+The [[tla]] support also needs the `MailTools` perl module.
+
+Various [[plugins]] use other libraries and utlities; see their individual
+documentation for details.
+
+If you're installing MarkDown by hand, note that it should be installed as
+`Markdown.pm` somewhere in perl's module search path, or alternately as
+`/usr/bin/markdown`. Ikiwiki will find it under either name.
+
+If you want to install from the tarball, you should make sure that the
+required perl modules are installed, then run:
+
+ perl Makefile.PL # PREFIX=/dir to install elsewhere