How I do Django-esque formsin Rails

ar_forms.rb

# Borrowing the idea for this from http://pivotallabs.com/users/jdean/blog/articles/1706-form-backing-objects-for-fun-and-profit
class Forms::Base
  # ActiveModel plumbing to make `form_for` work
  extend ActiveModel::Naming
  include ActiveModel::Conversion
  include ActiveModel::Validations

  def persisted?
    false
  end
end

# A specific form model
class Forms::UserProfile < Forms::Base

  def initialize(user)
    @user = user
  end

  attr_reader :user

  delegate :username, :username=, to: :user
  delegate :dont_index_me_bro, :dont_index_me_bro?, :dont_index_me_bro=, to: :user

  delegate :errors, to: user

  attr_accessor :profile_image_source

  def full_name
    user.full_name || user.first_name
  end

  def full_name=(new_name)
    user.full_name = new_name
    user.first_name = new_name.split(' ')[0]
  end

  def save
    user.save
  end
end