dryer_examples.rb

# app/models/user.rb

Dryer.def_class(__FILE__) do
  def hi
    "hello world"
  end
end

User.new.hi
=> "hello world"

# app/models/instruments/horn.rb

Dryer.def_class(__FILE__) do
  def play
    "toot!"
  end
end

Instruments::Horn.new.play
=> "toot!"

# app/models/address.rb

Dryer.def_class(__FILE__, ActiveRecord::Base) do
end

Address.new.respond_to? :save
=> true