Magento 1.0 launched in early 2008, has grown to 200k+ installations, and powers billions in eCommerce transactions each year. Though Magento 1 was one of the most sophisticated, flexible MVC architectures when it was released, PHP and development practices have evolved. This talk is a dive into the architectural decisions that are shaping Magento 2, including standardisation on Composer, use of AOP, and converting the application to have a full DI framework, and provide all business logic via a service layer.