The grand challenge in Digital Transformation is the implementation of fundamental changes in the way we carry out our business. In this paper we present a case of digital transformation implementing a customer-centric solution in a medium-sized European financial tech-company servicing eight medium-sized and smaller banks. From an analysis of the case, we elicit four design principles for Digital Transformation. We call them the strategizing principle, the showcasing principle, the digital mindfulness and the scaling principle. Finally, we discuss the four design principles in a description of how other organizations can use the principles to achieve digital transformation success.