class User < ActiveRecord::Base
  subscribe_to "List Name", :using => { :api_key => MAILCHIMP_API_KEY,
                                        :email => :email, 
                                        :fields => {:FNAME => :first_name, :LNAME => :last_name}}
end

When User is saved, it will be added to your MailChimp list “List Name”.

This assumes that you have @user.email, @user.first_name, @user.last_name setup as your models attributes. MailChimp expects FNAME, and LNAME, you can also specify any custom fields and they will be captured.

When User is deleted it will automatically be unsubscribed from “List Name”.

• hominid gem

gem 'hominid'
gem 'mailchimp_subscriber'

BSD License