Feature-Based Variability Management for Scalable Enterprise Applications: Experiences with an E-Payment Case

In today's world of electronic payments, which includes credit cards, gift cards, stored value accounts, and micro payments on mobile devices, successful payment services need to be sufficiently scalable and support diverging use cases to be successful. However, the interaction between horizontal scalability, feature variability and stringent performance and security concerns for these heterogeneous payment applications and stakeholders is not always clear, which creates tension (and sometimes interference) in the successful development of these services. In this work, we identify crucial non-functional requirements for payment services and present a simple framework to map these requirements to existing approaches to achieve both horizontal and vertical scalability. We report on experiences with applying a service line engineering (SLE) approach towards payment services that combines cloud computing and SPL to support feature customization in a multi tenant payment service. We conclude with practical experiences and several lessons learned after applying this SPL engineering methodology on our industrial e-payment use case.