Hexagonal Rails with Response Object: https://groups.google.com/d/msg/objects-on-rails/yY4k86n_i9s/dJcMiOYie34J

hexagonal.rb

class UsersController < ApplicationController 

  def create 
    CreateUser.new(User).call(params[:user], CreateResponse.new(self))
  end

  class CreateResponse < SimpleDelegator
    def user_created(user)
      flash[:notice] ="The user was created successfully" 
      redirect_to :index

    end

    def user_creation_failed(user)
      render 'new', locals: { user: user }

    end
  end
end

class CreateUser
   def initialize(users_repository)
     @users_repository = users_repository
   end

   def call(attributes: {}, listener)
      user = @users_repository.new attributes

      if user.save
        listener.user_created(user)

      else
        listener.user_creation_failed(user) unless user.save
      end
   end
end

Similar option to what I have been exploring recently, factory for use cases:

https://gist.github.com/chris-zwickilton/6625578
https://groups.google.com/d/msg/objects-on-rails/yY4k86n_i9s/lNzigifGL6AJ