Gemfile

source "https://rubygems.org"

gem 'faraday'
gem 'faraday_middleware'
gem 'active_support'

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    active_support (3.0.0)
      activesupport (= 3.0.0)
    activesupport (3.0.0)
    faraday (0.8.7)
      multipart-post (~> 1.1)
    faraday_middleware (0.9.0)
      faraday (>= 0.7.4, < 0.9)
    multipart-post (1.2.0)

PLATFORMS
  ruby

DEPENDENCIES
  active_support
  faraday
  faraday_middleware

test.rb

require 'rubygems'
require 'bundler/setup'

require 'active_support'
require 'faraday'
require 'faraday_middleware'

conn = Faraday.new('https://www.google.com') do |conn|
  conn.use :instrumentation
end
puts conn.get('/').body

conn = Faraday.new('https://www.google.com') do |conn|
  conn.use :instrumentation
  conn.adapter Faraday.default_adapter
end
puts conn.get('/').body