Lutz Kettner leads the design and engineering efforts for the Material Definition Language, MDL, and the Iray renderer from the NVIDIA Advanced Rendering Center. He has been working on leading software products in advanced rendering, language design, API design, and geometry for 19 years. He is known for his influential work on the open source Computational Geometry Algorithms Library, CGAL. He holds a Ph.D. in computer science from ETH Zurich, Switzerland, worked as a researcher at the University of North Carolina at Chapel Hill, and led a research group at the Max-Planck-Institute in Saarbrucken, Germany. He has also served on ISO and ECMA standardization committees.