If you want your implementation to conform to an architecture, then it must conform to the design decisions prescribed by the architecture. It must have the set of elements prescribed by the architecture, these elements must interact with each other in the fashion prescribed by the architecture, and each element must fulfill its responsibility to... See more

• If your system requires high performance, then you need to pay attention to managing the time-based behavior of elements, their use of shared resources, and the frequency and volume of their interelement communication.


• If modifiability is important, then you need to pay attention to assigning responsibilities to elements and limiting the

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Once an architecture has been defined, it can serve as the basis for incremental development. The first increment can be a skeletal system in which at least some of the infrastructure—how the elements initialize, communicate, share data, access resources, report errors, log activity, and so forth—is present, but much of the system’s application... See more

Every architecture, no matter what it is, partitions possible changes into three categories: local, nonlocal, and architectural.

• A local change can be accomplished by modifying a single element—for example, adding a new business rule to a pricing logic module.


• A nonlocal change requires multiple element modifications but leaves the underlying

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Decisions at all stages of the life cycle—from architectural design to coding and implementation and testing—affect system quality. Therefore, quality is not completely a function of an architectural design. But that’s where it starts.

once the architecture has been agreed upon, it becomes very costly—for managerial and business reasons—to significantly modify it. This is one argument (among many) for analyzing the software architecture for a large system before settling on a specific choice.

The software development community is coming to grips with the fact that roughly 80 percent of a typical software system’s total cost occurs after initial deployment. Most systems that people work on are in this phase. Many programmers and software designers never get to work on new development—they work under the constraints of the existing... See more

The benefits of incremental development include a reduction of the potential risk in the project. If the architecture is for a family of related systems, the infrastructure can be reused across the family, lowering the per-system cost of each.

Many systems are built as skeletal systems that can be extended using plug-ins, packages, or extensions. Examples include the R language, Visual Studio Code, and most web browsers.