Codifying architecture knowledge to support online evolution of software product lines

A company's architecture knowledge is often personalized across specific people that share experience and knowledge in the field. However, this knowledge may be important for other stakeholders. Omitting the codification of the architecture knowledge may result in ad-hoc practices, which is particularly relevant for software evolution. In a collaboration with Egemin, an industrial manufacturer of logistic systems, we faced the problem with a lack of codified architecture knowledge in the context of the evolution of a software product line (SPL). In particular, maintainers lack the architecture knowledge that is needed to perform the evolution tasks of deployed products correctly and efficiently. Ad-hoc updates increase costs and harm the company's reputation. To address this problem, we developed an automated approach for evolving deployed systems of a SPL. Central in this approach are (1) a meta-model that codifies the architecture knowledge required to support evolution of a SPL, and (2) and algorithm that uses the architecture knowledge harvested from a deployed system based on the meta-model to generate the list of tasks maintainers have to perform to evolve the system. Evaluation of the approach demonstrates a significant improvement of the quality of system updates with respect to the correct execution of updates and the availability of services during the updates.