Architecture-level modifiability analysis (ALMA)

Several studies have shown that 50–70% of the total lifecycle cost for a software system is spent on evolving the system. Organizations aim to reduce the cost of these adaptations, by addressing modifiability during the system’s development. The software architecture plays an important role in achieving this, but few methods for architecture-level modifiability analysis exist. Independently, the authors have been working on scenario-based software architecture analysis methods that focus exclusively on modifiability. Combining these methods led to architecture-level modifiability analysis (ALMA), a unified architecture-level analysis method that focuses on modifiability, distinguishes multiple analysis goals, has explicit assumptions and provides repeatable techniques for performing the steps. ALMA consists of five main steps, i.e. goal selection, software architecture description, change scenario elicitation, change scenario evaluation and interpretation. The method has been validated through its application in several cases, including software architectures at Ericsson Software Technology, DFDS Fraktarna, Althin Medical, the Dutch Department of Defense and the Dutch Tax and Customs Administration. 2003 Elsevier Inc. All rights reserved.