Iterative and incremental development of component-based software architectures

While the notion of components has had a major positive impact on the way software architectures are conceptualized and represented, they have had relatively little impact on the processes and procedures used to develop software systems. In terms of software development processes, use case-driven iterative and incremental development has become the predominant paradigm, which at best ignores components and at worse is even antagonistic to them. However, use-case driven, I&I development (as popularized by agile methods) and component-based development have opposite strengths and weaknesses. The former's techniques for risk mitigation and prioritization greatly reduce the risks associated with software engineering, but often give rise to suboptimal architectures that emerge in a semi-ad hoc fashion over time. In contrast, the latter gives rise to robust, optimized architectures, but to date has poor process support. In principle, therefore, there is a lot to be gained by fundamentally aligning the core principles of component-based and I&I development into a single, unified development approach. In this position paper we discuss the key issues involved in attaining such a synergy and suggest some core ideas for merging the principles of component-based and I&I development.