An enterprise architecture is a set of decisions about what should stay together, what can change independently, and how the parts connect. The value of those decisions becomes visible when the business needs to move.
Start with the business boundary.
A technology boundary is easy to draw. A useful business boundary takes more thought. Which rules belong together? Who owns the decision? What must remain consistent when a process crosses systems?
Those questions help determine the shape of a service or module. Starting with them gives the architecture a purpose beyond the technology used to implement it.
Make connections explicit.
Every connection introduces a dependency. APIs, events, and shared data all carry assumptions about behavior. Clear contracts make those assumptions visible, including what happens when an operation fails or a downstream system is unavailable.
That clarity matters to both development and operations. A system is easier to reason about when its responsibilities, error paths, and ownership are understandable.
Choose independence deliberately.
Modularity is not a mandate to split everything into microservices. Each boundary adds coordination and operational work. The right design depends on the business capability, the team, and the need for independent change.
Sometimes a well-structured application is the right foundation. Sometimes a capability needs its own service. The important decision is why a boundary exists, not how many boundaries the system has.
Keep the next decision possible.
No architecture can predict every future requirement. It can make some changes less entangled by separating business rules from delivery mechanisms and infrastructure.
At Firefly, that is a guiding principle: build around the business today while keeping the next important decision possible.