Hello, my name is Onur Eren Arpacı. I am a Research Associate in the Cryptography, Security, and Privacy (CrySP) lab at the University of Waterloo, where I work with Florian Kerschbaum and Sujaya Maiyya. I hold a master’s degree in Computer Science from the University of Waterloo and a Bachelor of Science in Computer Engineering from Koç University.

My research addresses privacy in systems that compute on data without seeing it. I design efficient private set intersection protocols, so parties learn what their sets have in common and nothing else. I also build oblivious storage systems, where the access pattern stays hidden along with the data. Most of my work is about closing the gap between what is provably private and what is practical to deploy.

Currently, I am working on a highly efficient fuzzy private set intersection protocol, where parties learn which of their items are close to one another rather than identical, and nothing else. Most recently, Cloak, an oblivious storage system I built with Florian Kerschbaum and Sujaya Maiyya, was accepted to the IEEE Symposium on Security and Privacy 2027. It gets its speed from the temporal locality of real workloads. Previously, I worked with Raouf Boutaba and Florian Kerschbaum on over-threshold multiparty private set intersection for collaborative network intrusion detection, which grew out of my master’s thesis and was published at NSDI ’26.

In my free time, I make financially irresponsible decisions about coffee brewing gear, design useful things to print on my 3D printer, and go on trips with my best friend Beryl (who also happens to be my fiancée) and our cat Künefe.