BUNDLE_FROZEN是一个常用的环境变量，在开发Ruby on Rails应用程序时，可以被用来设置运行时Bundle的安装位置以及构建应用程序时使用的gem版本。

使用BUNDLE_FROZEN，需要在应用程序的Gemfile中添加以下代码：

source 'https://rubygems.org'

ruby '2.6.3'

Set the Rubygems source to avoid timeouts

#rubygems_sources = ENV['RUBYGEMS_SOURCE'] || 'https://rubygems.org' #source rubygems_sources, :ssl_verify_mode => OpenSSL::SSL::VERIFY_PEER

Bundle edge Rails instead: gem 'rails', github: 'rails/rails'

gem 'rails', '~> 5.2.0'

Use postgresql as the database for Active Record

gem 'pg', '>= 0.18', '< 2.0'

Use Puma as the app server

gem 'puma', '~> 3.0'

Use SCSS for stylesheets

gem 'sass-rails', '~> 5.0'

Use Uglifier as compressor for JavaScript assets

gem 'uglifier', '>= 1.3.0'

See https://github.com/rails/execjs#readme for more supported runtimes

gem 'therubyracer', platforms: :ruby

Use CoffeeScript for .coffee assets and views

gem 'coffee-rails', '~> 4.2'

Use jquery as the JavaScript library

gem 'jquery-rails'

Turbolinks makes navigating your web application faster. Read more: https://github.com/turbolinks/turbolinks

gem 'turbolinks', '~> 5'

Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder

gem 'jbuilder', '~> 2.5'

Use Redis adapter to run Action Cable in production

gem 'redis', '~> 4.0'

Use ActiveModel has_secure_password

gem 'bcrypt', '~> 3.1.7'

group :development, :test do

Call 'byebug' anywhere in the code to stop execution and get a debugger