Bundler provides a consistent environment for Ruby projects by tracking and installing the exact gems and versions that are needed.
Bundler is an exit from dependency hell, and ensures that the gems
you need are present in development, staging, and production.
Starting work on a project is as simple as bundle install.
Getting started with bundler is easy! Specify your dependencies in a Gemfile in your project's root:
source 'https://rubygems.org'
gem 'nokogiri'
gem 'rack', '~> 2.2.4'
gem 'rspec'Install all of the required gems from your specified sources:
$ bundle install
$ git add Gemfile Gemfile.lock