HPI Alumni Day

Prof. Dr. Ziawasch Abedjan

Chair of the Data Integration and Data Preparation group, BIFOLD and TU Berlin

Ziawasch Abedjan is Chair of the Data Integration and Data Preparation group at BIFOLD and TU Berlin. His research is focused on developing machine learning- based and scalable techniques for various data integration, such as data cleaning, data science pipelines, and data discovery.

Ziawasch received his PhD from the Hasso Plattner Institute in Potsdam, Germany and spent two years as a postdoctoral associate at MIT. From 2016 - 2020 he was Junior Professor at the TU Berlin and senior researcher at DFKI. 2020 he was appointed Full Professor and Chair of the „Datenbanken und Informationssysteme“ group at Leibniz Universität Hannover. He spent two years as visiting academic at Amazon Search. His research is supported by the DFG and the Federal Ministry of Science and Education.

Prof. Dr.-Ing. Bert Arnrich

Chair in Digital Health - Connected Healthcare, Hasso Plattner Institute

Prof. Dr.-Ing. Bert Arnrich is Professor for Digital Health - Connected Healthcare at the joint Digital-Engineering Faculty of Hasso Plattner Institute (HPI) and the University of Potsdam.
  
His research on ubiquitous sensing and computing technologies is directed towards paving the way for transforming healthcare systems from purely managing illness to maintaining wellness everywhere, anytime and for anyone. He has been a PI in several European and national research projects.

He studied "Informatics in the Natural Sciences" and received the PhD degree Dr.-Ing. for the thesis "Data Mart Based Research in Heart Surgery". He established and headed the research group Pervasive Healthcare in the Wearable Computing Laboratory at ETH Zurich. He received a Marie Curie Cofound Fellowship from the European Union and was appointed to tenure track professorship at the Computer Engineering Department at Bosporus University.  He worked as a Science Manager for Emerging Technologies at Accenture Technology Solutions.

Prof. Dr. Niclas Böhmer

Assistant Professor for Algorithmic Decision Making and Society, Hasso Plattner Institute

Niclas Böhmer is an Assistant Professor for Algorithmic Decision Making and Society at the Hasso Plattner Institute, University of Potsdam. Previously, Niclas completed a postdoc at Harvard University, focusing on AI for Social Good, and a PhD in theoretical computer science at TU Berlin. In his work, Niclas designs and analyzes algorithms that make “fair” decisions for groups of individuals with competing interests.

Stefan Bunk

Founder and CTO, Vara

Stefan Bunk is the founder of Vara, a leading healthcare company transforming early breast cancer detection through artificial intelligence. After graduating from the Hasso Plattner Institute in 2017 with a specialization in applied machine learning, software engineering, and healthcare IT, Stefan joined Merantix for a year before founding Vara in 2018.

Under Stefan's leadership, Vara has become an integral part of Germany's mammography screening program, supporting over 40% of all screenings and providing high-quality screening to over 1 million women annually. The company conducted the groundbreaking PRAIM study, published in Nature Medicine, which represents the largest prospective study on the real-world effectiveness of AI in healthcare to date, involving half a million participants.

Using Vara's technology, the PRAIM study demonstrated significant improvements in cancer detection rates and reductions in false-positive rates, leading to earlier diagnoses and fewer unnecessary procedures. This research showcases the transformative potential of AI to enhance breast cancer screening outcomes while reducing patient anxiety and healthcare costs. Stefan's work at Vara reflects his dedication to creating practical solutions to critical healthcare challenges, bridging the gap between cutting-edge AI research and real-world medical applications that directly improve patient care.

Prof. Dr. Tobias Friedrich

Professor, Dean and Managing Director, Hasso Plattner Institute

Tobias Friedrich, PhD, has led the research group on Algorithm Engineering at the Hasso Plattner Institute since 2015. In 2021, he was appointed Dean of the Faculty of Digital Engineering at the University of Potsdam, and in 2023, he became Managing Director of the Hasso Plattner Institute. Prior to joining HPI, he conducted research at the intersection of mathematics and theoretical computer science, with positions in Jena, Saarbrücken, Berkeley, and Sheffield.

His research focuses on the design and analysis of algorithms, random structures, and complexity theory. He is particularly interested in bridging rigorous mathematical foundations with practically efficient algorithm design. Tobias has published several hundred peer-reviewed papers, received over ten best paper awards, and secured more than a dozen competitive research grants from the German Research Foundation and the European Union.

Martin Graf

Co-Founder and CTO, praxipal

Martin Graf is the co-founder and CTO of praxipal, where he and his team are building an AI workforce for healthcare front desks to tackle the growing shortage of medical staff. Their first product, Luna, is an AI receptionist that automates patient phone calls. praxipal is rapidly growing and backed by leading investors from the US, UK, and Europe.

Before founding praxipal, Martin studied IT Systems Engineering at Hasso Plattner Institute and Advanced Computer Science at the University of Cambridge. He has previously worked at Palantir and in health tech, and served as tech lead at an NGO.

Martin Karlsch

CO-Founder and CTO, Remerge

Martin Karlsch earned his M.Sc. in IT Systems Engineering from the Hasso Plattner Institute in 2006. Since then, he has co-founded several Berlin startups: Artmesh, Madvertise (acquired by MNG), LiquidM (acquired by Bertelsmann), and Remerge in 2014. At Remerge, where he serves as CTO, he helped grow the company from a five-person team into a global organization of more than 200 people, building a profitable business with nine-digit annual revenues.

Martin still enjoys diving into code when time allows, though most of his focus today goes into shaping high-performing engineering and data science teams. Outside of work, he is an active angel investor, tinkers with electronics, and seeks out new experiences and perspectives around the world.

Dr. Frank Keller

General Manager Large Enterprise & Merchant Platform, Paypal

As General Manager of PayPal’s Large Enterprise & Merchant Platform Group, Frank Keller oversees a global product portfolio that supports large and mid-sized merchants and partners in growing their business. Frank is responsible for the strategy and delivery of checkout and payment solutions that leverage PayPal’s two-sided network to drive customer success on a global scale.

Frank brings more than two decades of experience as a general manager and senior product executive to his role with PayPal. He joined the company in 2011 and has been in global senior leadership positions, managing a variety of functions across product and go-to-market including the transformation of PayPal’s global sales organization. He has also held various regional leadership roles, including General Manager of PayPal Germany, Austria, and Switzerland (DEATCH).

Throughout his tenure, Frank has focused on creating alignment across Product, Engineering, Sales, Marketing, and other functions to build high-performing teams that keep customer needs at the center. Additionally, he has managed and integrated multiple acquired companies, leading both successful acquisitions and divestures. 

Prior to joining PayPal, Frank founded and managed two startup IT companies in Berlin, Germany and worked in Malaysia on the launch of a mobile broadband network.

Frank holds a doctoral degree in Software Engineering from the Hasso Plattner Institute in Germany.

Nina Kiwit

Co-Founder, MindAhead

Nina Kiwit co-built two startups before pursuing her M.Sc. in Digital Health at the Hasso Plattner Institute - one in health tech and one in fintech. After graduation, she founded MindAhead, where she develops digital solutions for people with cognitive impairments. Her expertise lies in practical startup development and in implementing technological innovations in healthcare.

Georg Köster

VP Engineering,, Brighter AI Technologies GmbH

Georg Köster studied at the Hasso Plattner Institute, EFREI Paris, and Stanford University in California. Another two years in China followed. He interned/student jobbed with SMEs, Credit Lyonnais, Google, SAP, and Siemens. Back in Germany in 2012-2013 he tried to start a video messenger, financed by his work for pidoco, a HPI startup. 2015 he joined SAP as staff engineer, as Blockchain and AI expert, and later engineering manager for the LoB Real Estate. Since 2022, at brighter AI, has been supporting the two founders with management of the engineering unit during several due diligence phases and the exit in 2025.

Stefan Krumnow

Co-Founder, addressable value

Stefan Krumnow has extensive leadership experience in B2B SaaS, most notably from his 16 years at Signavio, where he helped shape the company’s journey from a bootstrapped startup to a strategic SAP business unit. He joined Signavio as one of the first software engineers and built large parts of its initial product. Over seven years, he went on to establish and lead Signavio’s global post-sales organization as Senior Vice President in the go-to-market area. Later, he returned to his engineering roots to head a growing department of up to 18 scrum teams. Following the acquisition by SAP, Stefan played a key role in the post-merger integration of Signavio. 

In late 2025, he left SAP to co-found addressable value, a B2B SaaS company on a mission to boost the go-to-market performance of SaaS businesses and strengthen their position in the global marketplace.

Prof. Dr. Felix Naumann

Head of Information Systems, Hasso Plattner Institute

Prof. Felix Naumann has headed the Information Systems research group at the Hasso Plattner Institute in Potsdam since 2006. Together with his team, he develops methods for data analysis, data cleansing, and information integration. He is the author of over 200 scientific publications and has supervised numerous doctoral students.

After a two-year research stay at the IBM Almaden Research Center, he taught and conducted research as an assistant professor at Humboldt University of Berlin before joining HPI in 2006. Since then, he has been a visiting researcher at several international institutions.

He currently serves as Coordinator of the Data & AI Cluster at HPI and as Spokesperson of the HPI Research School “Information and Data Engineering.”

Lasse Steffen

Founder and CEO, koppla

Lasse Steffen graduated from the Hasso Plattner Institute in 2020. After gaining startup experience during his studies, he jumped straight into entrepreneurship, co-founding koppla with two close friends to fix the construction industry. That decision has shaped everything since—and it’s what continues to excite him today.

Katya Sumina

Senior Software Engineer and AI Agent Security, Google

Katya Sumina Hasso Plattner Institute’s Bachelor’s program in IT Systems Engineering in 2021. She is now a Senior Software Engineer at Google, based in their Zurich office. Katya works in AI agent security space. Previously, she spent years building high-load, scalable, globally distributed systems for Google Cloud. Before becoming a software engineer in her late 20s, she had a career in journalism and project management. Katya also holds an M.A. in Gender Studies.

Nicholas Wittstruck

Co-Founder, B310 Digital

Nicholas Wittstruck founded B310 Digital to help companies not only use open-source projects but actively contribute to them. Besides a strong focus on the education sector, B310 has grown to become one of the largest external contributors to GitLab, with projects for clients such as Siemens.

After studying at the Hasso Plattner Institute, Nicholas took on several leadership roles:
He began at EDEKA Digital, where he brought startups into the company’s ecosystem in the area of Innovation & New Ventures and helped shape the shopping experience of the future. He then led the shop and IT teams at Bringmeister, building a modern e-commerce system for grocery delivery. Later, as CTO of a PropTech startup, he built data science and engineering teams that enabled data-driven real estate valuations.

For his commitment to education and his role as an engineering mentor for Tech4Germany, Nicholas was named a Young Leader in GovTech in 2023 by Handelsblatt and Possible.

Dr. Johannes Wolf

Program Manager Computer Science, Hasso Plattner Institute

Johannes Wolf began his Bachelor’s degree in IT Systems Engineering at HPI in 2010. After completing an internship at SAP Labs in California, he continued his studies with a Master's degree in the same field. He then pursued his Ph.D. in the field of data analysis and visualization. Throughout his studies, he was an active member of the student representative group and served on several university committees. After completing his doctorate, he worked as a project lead on software development projects for public administration clients at an IT consulting firm. Since the introduction of the Master's program in Computer Science, Johannes has returned to HPI as an academic program manager. In this capacity, he is entrusted with the responsibility of meticulously orchestrating a prosperous academic journey for the majority of HPI's Master's students.

Dr. Nico Herzberg

Senior Manager Startup Co-Innovation & Innovation Ecosystem | Founder, Infineon Technologies Dresden AG & Co.KG | Stealth Deep Tech Startup

Dr. Nico Herzberg is a Startup Co-Innovation & Innovation Ecosystem Strategist with a passion for connecting research, technology, and entrepreneurship. After earning his PhD at the Hasso Plattner Institute, he continued his work at SAP, where he built innovation programs and led initiatives to support young professionals in developing digital skills and entrepreneurial thinking.

He later moved to Infineon Technologies, focusing on startup co-innovation and the creation of collaborative deeptech ecosystems that bridge corporates, SMEs, and research institutions. Alongside his corporate work, Nico has co-founded several startups in B2B and B2C. He also teaches digital innovation and entrepreneurship at universities and conducts applied research on the future of work and technology-driven transformation.

His current focus lies in exploring new approaches to chip prototyping and small-series manufacturing to strengthen Europe’s technological sovereignty. Driven by curiosity and a systems perspective, Nico’s work centers on one question: how can we turn knowledge into lasting impact?

Markus Güntert

Self-employed Product & Agile Coach

Self-employed Product & Agile Coach. I help CPOs, Product Managers and Product Owners to up their product game. 10+ years working experience with 20+ clients (Corporate Ventures, Innovation Labs, SMEs, Startups and Agencies). Love for strategy, number crunching, climbing and synthesizers.

Prof. Dr. Ralf Herbrich

Head of Artificial Intelligence and Sustainability, Hasso Plattner Institute

Ralf Herbrich leads the group on Artificial Intelligence and Sustainability at the Hasso Plattner Institute in Potsdam since May 2022. From 2022 to 2025, he also served as Managing Director of the Hasso Plattner Institute, where he led the HPI Partnerships Team as well as the School of Design Thinking and Entrepreneurship. Previously, he served as Senior Vice President, Builder Platform & Artificial Intelligence at Zalando (2020 – 2022), Managing Director of the Amazon Development Center in Germany with its locations in Berlin, Dresden, Aachen and Tübingen and was Director of Machine Learning at Amazon in Berlin from (2013 – 2020). Prior to these roles at Amazon, he led Facebook’s Unified Ranking and Allocation team in 2011. From 2000 to 2011, he served as Director of Microsoft's Future Social Experiences (FUSE) Lab UK and worked for nine years at Microsoft Research Lab in Cambridge, UK.

Prof. Dr. Christian Dörr

Chair of Cybersecurity and Enterprise Security, Hasso Plattner Institute

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Prof. Dr. Gerard de Melo

Chair of Artificial Intelligence and Intelligent Systems, Hasso Plattner Institute

Prof. Dr. Gerard de Melo is a professor at HPI and the University of Potsdam, where he holds the Chair for AI and Intelligent Systems and leads the corresponding research group. Previously, he was a faculty member at Rutgers University in the US and at Tsinghua University in Beijing, and a post-doc at ICSI/UC Berkeley. He has published over 200 papers on diverse aspects of AI, receiving a number of Best Paper awards. He also serves as the General Chair for the AI@HPI Conference and has been featured in the press numerous times. Further information is available at hpi.de/de-melo.

Marc Rosenau

Co-Founder, Cula Technologies

Marc is Co-Founder of Cula Technologies, an impact-tech startup that develops the digital infrastructure for Carbon Removal projects. Founded in 2022 from the first batch of HPI Ventures Builder, the company has rapidly scaled and now works with carbon removal projects across multiple technologies and over 20 countries, addressing critical challenges in the emerging carbon removal industry by providing end-to-end digital solutions for project tracking and certification, increasing transparency and efficiency along the whole value chain.

Marc developed his technical expertise during his IT Systems Engineering studies at Hasso Plattner Institute (Bachelor 2017-2020, Master 2020-2022) with a focus on Business Process Management and digital entrepreneurship. Both his thesis projects were completed at Prof. Weske's chair, and he additionally went through the innovative HPI Engine program.

As early as 2019, Marc founded the consulting agency Mr. Deliver, where he led various software projects and consultancy services until 2022, gaining valuable entrepreneurial experience. Parallel to his professional career, he volunteered for three years as an event organizer for HackHPI and was instrumental in organizing various tech events.

David Hahn

Head of Program, HPI Engine

David Hahn serves as Head of Program at HPI Engine, the Entrepreneurship Center of the Hasso Plattner Institute. He is responsible for designing and leading programs that foster innovation and entrepreneurial talent among students and researchers. With a background in computer science and extensive experience in innovation and startup coaching, he combines technological expertise with entrepreneurial practice to enable the creation of impactful digital ventures.