Include paper_trail for all the models.

paper_trail.rb

ActiveRecord::Base.module_eval do
  class << self
    def inherited_with_paper_trail(subclass)
      skip_models = %w(schema_migrations versions)

      inherited_without_paper_trail(subclass)

      table_name = subclass.table_name

      if !skip_models.include?(table_name) && table_name.present?
        subclass.send(:has_paper_trail)
      end
    end

    alias_method_chain :inherited, :paper_trail
  end
end

what is skip_models is for ..??

@Workoidz if you are using rails >= 5.2 then use the following trick:

class ApplicationRecord < ActiveRecord::Base
  self.abstract_class = true

  def self.inherited(subclass)
    super
    subclass.send(:has_paper_trail)
  end
end

And skip_models is used to ignore migrations and versions it self (as it doesn't required to make a versioning for those tables, and BTW versions will lead into a SystemStackError (stack level too deep)).