I am a PMC member of Apache Flink and contributing to Flink since its earliest days when it started as research project as part of my PhD at TU Berlin. I co-founded and work as a software engineer at data Artisans, a Berlin-based start-up devoted to foster Apache Flink. The focus of my work is on Flink's relational APIs, the Table API and SQL, which are unified APIs for batch and stream processing. I am interested in distributed data processing and query optimization. At the moment, I'm also writing a book on "Stream Processing with Apache Flink" for O'Reilly.