config.ru

# use local copy of sinatra
$LOAD_PATH.unshift File.dirname(__FILE__) + '/sinatra/lib'
 
require "rubygems"
require "sinatra"
 
# Map static files
use Rack::Static, :urls => ["/images", "/stylesheets", "/javascripts"], :root => "public"
 
# Map URLs to diffrent sinatra apps
map "/user/" do
    run Sinatra("app/user/user.rb")
end

user.rb

$:.unshift File.join(File.dirname(__FILE__), "..", "lib")
 
require 'rubygems'
require 'sinatra'
 
get '/' do
  "Hello World"
end