dynclass.rb

#!/usr/bin/env ruby

module ClassMixin

  def ping
    puts 'pong'
  end
end

module InstanceMixin
  def blip
    puts 'blop'
  end
end

class Minion
end

Minion.class_exec do
  include ClassMixin
end

the_minion = Minion.new
the_minion.ping

the_minion.extend InstanceMixin
the_minion.blip