# Terminal
brew install puma/puma/puma-dev
puma-dev -install
rails new app_name
cd app_name
puma-dev link -n app_name .
pkill -USR1 puma-dev
pry-remote

# welcome_controller.rb
class WelcomeController < ApplicationController
  def index
    10.times do |i|
      @instance = 'hello'
      local_var = 'world'
      # raise
      binding.remote_pry
    end
  end
end