Evolutionary Architecture: Embracing change in an Agile manner

The Rise of Design Patterns

Traditionally, the software architecture for systems was developed and completed before writing a single line of code. Over time, systems became harder to change resulting in an inability to adopt business requirements in a timely manner. To cope with these problems, we started considering maintainability and extensibility as characteristics of well-architected systems. This gave rise to Design patterns, S.O.L.I.D principles and, recently, the Agile and DevOps movements. The agile practitioners observed that change is a necessity and challenged the notion of fixed requirements. The business and technology landscape is constantly changing in response to market and regulatory changes. To adapt to the modern dynamism, we need to constantly evolve our architecture and incorporate feedback from stakeholders and customers.

Evolutionary Architecture

Evolutionary architecture is an “architecture that supports guided, incremental change across multiple dimensions”. This view of architecture embraces changes in an agile manner without losing the important architectural characteristics of the system. “The heart of doing evolutionary architecture is to make small changes, and put in feedback loops that allow everyone to learn from how the system is developing.” The feedback loops consist of a set of fitness functions used to measure and test the impact of change on specific characteristics as the system evolves. “Evolutionary architecture is not an unconstrained, irresponsible approach to software development. Rather, it is an approach that balances the need for rapid change and the need for rigor around systems and architectural characteristics.”. Some benefits of evolutionary architectures include reduced architectural complexity, increased business agility, increased quality and scalability, and reduced development cost.

Adapting to Change

The dynamic business landscape has made change hard to predict, and fixed plans are no longer an option. In order to support the business, we must learn to adapt and fully embrace change. By identifying important architectural characteristics and leveraging feedback loops, we can evolve the system over time without compromising those characteristics. This results in architectures that have no end state, instead, the architecture evolves over time to fully support the changing business and technology environments.

References

Ford, Neal, et al. Building Evolutionary Architectures: Support Constant Change. O’Reilly Media, Inc., 2017.