Separation of Concerns with Rails ActiveRecord custom callbacks

soc_with_custom_callbacks.rb

module Commentable
  extend ActiveSupport::Concern
  
  included do
    has_many :comments
    define_model_callbacks :comment_update, only: :after
  end
end

class Post
  include Commentable

  after_comment_update { touch(:comment_updated_at) }
end

class Comment
  belongs_to :commentable, polymorphic: true
  
  after_update { commentable.run_callbacks(:comment_update, :after) }
end