Modernizing an Existing System to Take a More Domain-Driven Approach

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.

Intro
What is DDD?
Core concepts
Domain
Model
Business ubiquitous language
Relationships
Implementation Concepts
Microservices
Messaging
Why eventual consistency matters
Command-Query Responsibility Segregation (CQRS)
When should you use Event Sourcing
Refactor Design Patterns
Strangler Fig
Branch by Abstraction
Parallel Run
Other Design Patterns for Refactoring
The business systems
Database Design
Creating an order - Call origination
Creating an Order - Inter-system communications
How do you even start with this???
Define your context and bounded contexts
Define your communication
Detail your communication
Planning your refactor
Starting your refactor
Old Approach - Inter-system communications
New Approach - Inter-system communications for a
The new business systems
Work to do to existing systems
Refactoring to be Done
Current Order Service