Domain specific languages play an important role in model-driven engineering of software-intensive industrial systems. A rich body of knowledge exists on the development of languages, modeling environments, and transformation systems. The understanding of architectural choices for combining these parts into a feasible solution, however, is not particularly deep. We report on an endeavor in the realm of a technology transfer process from academia to industry, where we encountered unexpected influences of the architecture on the modeling language. By examining the evolution of our language and its programming interface, we show that these influences mainly stemmed from practical considerations; for identifying these early on, tight interaction between our research lab and the industrial partner was key. In addition, we share insights into the practice of cooperating with industry by presenting essential lessons we learned.