Using Bundler with Sinatra
To use bundler with a Sinatra application, you only need to do two things. First, create a Gemfile.
gem 'sinatra'
Then, set up your config.ru file to load the bundle before it loads your Sinatra app.
require 'rubygems'
require 'bundler'
Bundler.require
require './my_sinatra_app'
run MySinatraApp
Start your development server with rackup, and Sinatra will be loaded via Bundler.
$ bundle exec rackup
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