Legacy system updates need more than just stakeholder input
When Stakeholder-centric Requirements Engineering is Not Enough: An Action Research Study on Legacy System Modernisation
Software Engineering
Summary
Updating old computer systems is hard because companies often don’t fully understand how these systems work. The authors studied a big energy company trying to modernize their system by talking to stakeholders to gather and prioritize needs. While this helped create clear and correct requirements, it was not enough to figure out how these needs matched the old system’s actual functions. The study shows that besides listening to people, companies also need careful, step-by-step analysis of the old system, using tools and evidence to reduce uncertainty during modernization.
legacy systemsrequirements engineeringstakeholder-centricsystem modernizationgap analysiselicitation interviewsDelphi methodMoSCoW prioritizationdigital transformationaction research
Authors
Ruward S. Karper, Damian A. Tamburri, Alessio Ferrari, Willem-Jan van den Heuvel
Abstract
Legacy system modernisation is a major challenge in digital transformation, especially when organisations depend on long-lived, business-critical systems that are only partly understood. In such context, organisations must define future needs while determining what current systems actually do and which functions to retain, adapt, or replace. Modernisation is therefore not only a technical challenge but also a requirements engineering (RE) problem, shaped by stakeholder perspectives. This study examines how far stakeholder-centric RE can support gap analysis between the system-as-is and the system-to-be in a legacy modernisation context. We conducted an action research study in a multinational energy company engaged in system modernisation. In the study, we applied stakeholder-centric RE practices, including stakeholder identification, semi-structured elicitation interviews, agreement-building through the Delphi method, and prioritisation with the MoSCoW method. The results show that this process was effective in producing requirements stakeholders generally viewed as understandable and correct, but less effective in achieving agreement on how elicited requirements mapped to legacy system functionality. The findings suggest that stakeholder-centric RE is necessary but not sufficient, pointing to the need for uncertainty-aware, iterative, and evidence-based modernisation practices that combine stakeholder perspectives with manual and tool-assisted analysis of legacy systems.