app.rb

#!/usr/bin/ruby

require 'rubygems'
require 'sinatra'
require 'haml'
require 'pathname'

get '*' do
        base = Pathname.new(File.dirname(__FILE__)).parent
        path = @params[:splat].first.gsub(/^\//, '')

        if path !~ /\/$/ then
                name = path + '.haml'
                file = base + name
                if file.file? && file.readable? then
                        return Haml::Engine.new(file.readlines.join('')).render
                end
        end

        status 404
end

set :run => false
set :environment => :cgi
Rack::Handler::CGI.run Sinatra::Application

exit;