The basics of having entirely separate Sinatra apps running on the same server.

app.rb

require 'sinatra/base'

class App < Sinatra::Base
  get '/' do
    'app'
  end
end

bar.rb

require 'sinatra/base'

class Bar < Sinatra::Base
  get '/' do
    'bar'
  end
end

config.ru

require './app'
require './foo'
require './bar'


map('/foo') { run Foo }
map('/bar') { run Bar }

run App

foo.rb

require 'sinatra/base'

class Foo < Sinatra::Base
  get '/' do
    'foo'
  end
end