Kiwi is a C implementation of the vast majority of MediaWiki's wikitext syntax. It currently takes input on stdin and presents output on stdout, and there is a Ruby FFI module for direct library use as well. The major advantages of this implementation are intended to be speed and memory footprint.

At the moment a 100 line wikitext file with fairly complex markup can be parsed in 5-6ms on a one year old Apple MacBook Pro.

Kiwi is running on the web at drasticcode.com. Check it out there for a better list of capabilities.

require "yapwtp"

parser = WikiParser.new

# Open the requested file, parse, capture text and templates
wikitext = parser.html_from_file("cnn.com.wt")
templates = parser.templates

templates.each do |template|
  template_file = File.join("templates", template[:name]) 
  if File.exist? template_file
    wikitext.gsub! /#{template[:replace_tag]}/, parser.html_from_file(template_file)
  end
end
puts wikitext