Josh Brody questions

Josh Brody answers

• How a chaining interface like Rails ActiveRecord is built?
• how to store temporary attributes on an Active Record model
• Attach active storage file to mailer
• $_POST not working. "Notice: Undefined index: username..." [duplicate]
• How to add a custom button on the ActiveAdmin show view?
• Default values for models in rails
• Rails select options - set first option as disabled, selected
• Ruby hook for method defined?
• Ask your team for your master key and put it in ENV["RAILS_MASTER_KEY"] on heroku deploy
• Differences between `any?` and `exists?` in Ruby on Rails?