Yawk, is "yet another wiki klone", written in gawk as a CGI script, the footprint is very small. And because of this, the performance turns out to be better than those PHP/Perl/Python ones on the slug. You need a web server supports running CGI scripts, minihttpd is used in the example below.

 # ipkg update
 # ipkg install minihttpd
 # ipkg install yawk
 # /opt/etc/init.d/S80minihttpd start

point your browser to http://slug:8084/cgi-bin/wiki.cgi/ or equivalent http://slug:8084/cgi-bin/wiki.cgi/wiki-wiki/ and start adding wiki pages.

If you need a new yawk wiki space, all you need to do is just

 # echo "dir /opt/share/yawk-wikispace/foo-wiki" > /opt/etc/yawk/foo-wiki.conf
 # mkdir /opt/share/yawk-wikispace/foo-wiki

chown or chmod /opt/share/yawk-wikispace/foo-wiki so the user web server run under can write

Now you can access http://slug:8084/cgi-bin/wiki.cgi/foo-wiki/

The wiki syntax is a little different than the usual ones and taking some used to, see WikiFormatting as reference.