Begin Refactoring Monolithic Applications

Introduction to Domain-Driven Design on AWS: Refactoring Monolithic Applications

This post introduces Domain-Driven Design (DDD) on AWS, focusing on identifying business domains within legacy monolithic applications and decomposing them into microservices. Adopting a DDD approach for microservices enables businesses to leverage cloud scalability in their refactored applications. AWS recently announced the general availability of AWS Migration Hub – Refactor Spaces, a feature that facilitates implementing the strangler fig pattern to operate both legacy and refactored applications across multiple AWS accounts.

Benefits of Microservices Companies are increasingly looking to transform legacy monolithic applications into microservices for benefits such as increased business and technical agility, scalability, and resiliency. Microservices are less complex to manage, scale independently, and are more resilient to failures, enhancing overall customer experience.

Challenges of Refactoring

Refactoring applications can be challenging, especially in identifying the domains for each microservice. Different patterns can be applied to identify these domains, such as transaction type, organizational teams, or business subdomains. Each pattern has its advantages and challenges in terms of maintainability and alignment with business goals.

Domain-Driven Design Principles

DDD principles can help decompose a monolith by business subdomains. Event storming and context mapping are two approaches that can be used to identify these subdomains and how they correspond to services. Once subdomains are defined, implementing a new microservices architecture optimized for the cloud becomes feasible.

AWS Migration Hub Refactor Spaces

AWS Migration Hub Refactor Spaces allows for the incremental refactoring of monoliths into microservices using the strangler fig pattern. This approach enables businesses to operate both legacy and refactored applications concurrently, gradually routing traffic to the new services.

Conclusion

DDD principles, coupled with AWS services like Migration Hub Refactor Spaces, offer a structured approach to refactoring monolithic applications into microservices. This approach not only enhances scalability and agility but also aligns services with defined business goals, resulting in improved customer satisfaction and business agility.