Cloud-native systems are commonly built using Reactive Microservices. In the Lightbend Reactive Architecture: Foundations learning path, we discovered what makes a system Reactive. Now, in the Lightbend Reactive Architecture: Advanced learning path we will take that a step further. We will learn about some of the problems that are introduced when we start building distributed systems, and solutions that can help us overcome those problems. We will learn about the impact of the CAP theorem, and the laws of scalability. We will explore new patterns such as sharding, conflict-free replicated data types (CRDTs), sagas, and command query responsibility segregation (CQRS). These new ideas will help us build the next generation of systems that will allow us to scale beyond what we previously thought possible.