The document discusses strategies for evolving monolithic applications into microservice architectures. It notes that modern software needs to meet increasing demands around release frequency, developer velocity, and infrastructure costs. While classical architectures based on monoliths and service-oriented architectures were effective, they no longer address today's challenges. The document then introduces microservices as an alternative, describing characteristics like independent deployability, language/data agnosticism, and process isolation. It acknowledges that while building individual microservices is straightforward, the difficult part is designing the overall system architecture and operational capabilities required to manage many interconnected microservices. Lagom is presented as one framework that can help implement reactive microservices on the JVM.