Explore a comprehensive conference talk on modernizing existing enterprise systems using domain-driven design (DDD) principles. Learn about refactoring patterns that support this transition, including the Strangler Fig, Branch by Abstraction, and Parallel Run. Discover the core concepts of DDD, such as domain models, ubiquitous language, and bounded contexts. Delve into implementation concepts like microservices, messaging, eventual consistency, and Command-Query Responsibility Segregation (CQRS). Follow a step-by-step guide on how to approach refactoring, from defining contexts to planning and executing the modernization process. Gain insights into the decisions that need to be made and their impact on the overall refactoring strategy.