Non-Functional Architecture

Functional architecture contains business behavior: states, transitions, rules, and handlers. Non-functional architecture (NFA) contains infrastructure that makes this behavior executable.

NFA does not understand the business domain. It does not know what a patient is, what a visit is, or what an appointment means.

Non-functional architecture does not understand the business. It understands how work moves through the system.

What NFA Is Responsible For

NFA provides the technical services that functional components need in order to run:

• Receiving incoming work from user interfaces, APIs, or other systems
• Building and transporting data containers
• Serializing and deserializing data for communication
• Routing work to the correct handlers using metadata
• Executing transitions through the pipeline of logical layers
• Managing configuration, deployment, and operational concerns
• Logging, monitoring, error handling, security, and communication

The key point is that these responsibilities are generic. They apply regardless of the business domain being executed.

How NFA Works With Functional Architecture

Functional components (state handlers and transition handlers) implement business responsibility. NFA connects them together so that a business process can execute end-to-end.

In this architecture, a unit of work is represented as a data container that carries both business data and routing metadata.

NFA uses that metadata to determine:

• Which handler should receive the work
• Which logical layer should execute next
• Whether the work should continue or return control to a state handler

The functional handler performs business work. NFA performs coordination.

Management System and Request Redirector

In this book, NFA is represented by two key infrastructure components:

• Management system – coordinates execution and keeps the system operational.
• Request redirector – routes work to the correct handler based on metadata.

You can think of the management system as the conductor of an orchestra. It does not play instruments. It ensures that the right instruments play at the right time.

Why This Separation Matters

When functional architecture is isolated from NFA:

• Business components remain readable and testable.
• Infrastructure can evolve without rewriting functional components.
• The system can move toward distribution without redesigning functional architecture.

The separation is not theoretical. It prevents the business domain from becoming locked into a specific framework, deployment platform, or communication technology.

Summary

Non-functional architecture provides execution infrastructure. It coordinates how work flows through the system without interpreting its meaning.

Functional architecture provides business behavior. NFA makes it run without becoming part of it.

Table of Content Software Architecture Previous: Functional Architecture Next: Runtime Handler Discovery