Jędrzej Kołodziejski is a third-year PhD student at the Faculty of Matematics, Informatics and Mechanics, University of Warsaw - supervised by prof. Mikołaj Bojańczyk. He did both his BA and MA in Philosophy - as part of interdisciplinary studies at the University of Warsaw. His research interests are mainly logic, games and automata, with a special focus on bisimulation-invariant formalisms and model theory.