Dimitris Kontokostas is a lead software engineer at the Diffbot Knowledge Graph. Before Diffbot, he was the technical lead of the GeoPhy Data Platform. Dimitris has a PhD (Dr.-Ing.) from Leipzig University (AKSW/KILT Group) on "Large-scale knowledge extraction, publishing and quality assessment" where he graduated with magna cum laude. He served as the head of technical developments of DBpedia for three years, is the creator of RDFUnit, a unit testing framework for RDF with high industry uptake, heavily involved with data quality standardization activities (i.e. SHACL, ShEx) and a co-author of the “Validating RDF data" book.