Dr. Mohammad Hajarian is Research Faculty (Tenure) and Head of the AI-HCI Lab at ISTAR–Iscte, Iscte – University Institute of Lisbon. He is a former Marie Skłodowska-Curie Postdoctoral Fellow (CONEX-Plus) and previously held a tenure-track Assistant Professor position at Universidad Carlos III de Madrid (UC3M), where he led the EU-funded ROSNUB project. His research develops and validates human-centered methods for safer and more resilient digital ecosystems—spanning online social networks, gamification, HCI, interaction/experience design, personalization, recommender systems, AI-driven behavioral interventions, user engagement, and practical approaches to misinformation and online-hostility reduction. He is also the Founder & CEO of Gegli (Gohardasht.ir), one of the earliest social networks (launched in 2003), which he uses as a real-world research and innovation testbed to deploy and evaluate algorithms at scale. This living-lab approach enables longitudinal, real-world evidence—often difficult to obtain in lab-only studies—and supports collaborative research with international partners to implement and validate cutting-edge methods in operational environments. Across academic and industrial settings, he has contributed to industrial software projects and actively collaborates on Horizon Europe and industry-driven initiatives. He has delivered invited talks, workshops, tutorials, and conference presentations internationally, and he contributes to the research community as an editor and reviewer for leading journals and conferences. He has 50+ publications and books in computer science and software engineering, 10+ years of university teaching experience (including 35+ courses), and supervision of MSc/PhD theses, many resulting in peer-reviewed outputs. In recognition of his contributions, he has received multiple honors and awards, and his innovations have been adopted across research and industry contexts.