test.rb

require 'active_support'

module ImageUtils
  extend ActiveSupport::Concern

  module ClassMethods
    def clean_up
      puts "Cleaning up"
    end
  end
end

module ImageProcessing
  extend ActiveSupport::Concern
  include ImageUtils

  included do
    clean_up
  end
end

class Image
  include ImageProcessing
end

puts "making new image"

Image.new