Implementing e-commerce is complicated because there are several interconnected parts as: * Architectural Design and Patterns * Appropriate use of messaging, composition and inheritance * Balancing the transactions security and the user experience * Integration with 3rd-party services * Clear conversion funnel/workflow for ensuring business viability * Features management and implementation * I18n and localization * Continuos Integration and Deployment * Support and maintenance of e-commerce infrastructure We as a team focus in e-commerce implementation. Since several years ago, we have successfully implemented e-commerce for several customers, using Ruby, Ruby on Rails, Sinatra, Spreecommerce and other frameworks and platforms. We have learned many things in the process and we have identified common pitfalls and challenges. In this talk, those lessons learned will be presented, as well, how to implement a successful e-commerce.