addon.rb

module Addon
  def self.included(base)
    base.class_eval do
      before_save :update_addon
    end
  end

  def update_addon
    puts "updating addon"
  end
end

base.rb

class Base
  def self.callback_chain
    @callback_chain ||= Hash.new {|k,v| k[v] = [] }
  end

  def self.before_save(callback_method_symbol, options = nil)
    callback_chain[:before_save] << {callback_method_symbol => options || {}}
  end

  def self.after_save(callback_method_symbol, options = nil)
    callback_chain[:after_save] << {callback_method_symbol => options || {}}
  end
end

callback_research.rb

module CallbackResearch
  ARCA_CALLBACK_FINDER_REGEXP = /\A(.+)\:(\d+)\:in\s`.+'\z/
  private_constant :ARCA_CALLBACK_FINDER_REGEXP

  def self.included(base)
    callback_file_path, = caller[0].partition(":")

    base.class_eval do
      define_singleton_method(:callback_research_data) do
        @callback_research_data ||= Hash.new {|k,v| k[v] = [] }
      end

      [:before_save, :after_save].each do |callback_symbol|
        callback_method = singleton_class.instance_method(callback_symbol)

        define_singleton_method(callback_method.name) do |*args|
          line = caller.first
          callback_file_path, callback_line_number = ARCA_CALLBACK_FINDER_REGEXP.match(line)[1..2]

          caller.each do |line|
            if match = /\A(.+):\d+:in\s`<class:#{name.split("::").last}>'/.match(line)
              self.callback_research_data[:model_file_path] = match[1]
              break
            end
          end

          options = args.dup
          callback_research_data[callback_symbol] << {
            options.shift => (options.last || {}).merge({
              :callback_file_path => callback_file_path,
              :callback_line_number => callback_line_number.to_i,
              :model_class_name => name
            })
          }
          callback_method.bind(self).call(*args)
        end
      end
    end
  end
end

foo.rb

class Foo < Base
  def initialize
    @instance_state = "hello world"
  end

  before_save :blang

  def save
    self.class.callback_chain.each do |key, value|
      value.each do |callback_details|
        puts "#{key}: #{callback_details}, #{@instance_state}"
      end
    end
  end
end

runner.rb

require_relative "base"
require_relative "callback_research"

class Base
  include CallbackResearch
end

require_relative "foo"
require_relative "bar"

puts "analyzing Foo"
puts Foo.callback_research_data
puts ""
puts "analyzing Bar"
puts Sub::Bar.callback_research_data
puts ""
puts "testing Foo"
Foo.new.save
puts ""
puts "testing Bar"
Sub::Bar.new.save

$ ruby runner.rb 
analyzing Foo
{:model_file_path=>"/Users/jonmagic/Projects/ruby-composition/foo.rb", :before_save=>[{:blang=>{:callback_file_path=>"/Users/jonmagic/Projects/ruby-composition/foo.rb", :callback_line_number=>6, :model_class_name=>"Foo"}}]}

analyzing Bar
{:model_file_path=>"/Users/jonmagic/Projects/ruby-composition/sub/bar.rb", :before_save=>[{:update_addon=>{:callback_file_path=>"/Users/jonmagic/Projects/ruby-composition/addon.rb", :callback_line_number=>4, :model_class_name=>"Sub::Bar"}}], :after_save=>[{:ding=>{:if=>:dong?, :callback_file_path=>"/Users/jonmagic/Projects/ruby-composition/sub/bar.rb", :callback_line_number=>7, :model_class_name=>"Sub::Bar"}}]}

testing Foo
before_save: {:blang=>{}}, hello world

testing Bar
before_save: {:update_addon=>{}}, 
after_save: {:ding=>{:if=>:dong?}},