PhD Position in Declarative Problem Solving

This fully-funded PhD position at KU Leuven invites applications from motivated researchers interested in declarative problem solving and combinatorial optimization. The position is based in Prof. dr. Bart Bogaerts' research group, part of the Declarative Languages and Artificial Intelligence (DTAI) section within the Department of Computer Science. The group focuses on knowledge representation, proof logging, and explanations for combinatorial solving, aiming to develop methodologies and tools that guarantee correctness and reliability in solving complex optimization problems. Research directions include proof logging, where solvers produce machine-verifiable certificates of correctness, and explanations, which help users understand the reasoning behind solver decisions. The project seeks to address limitations in current proof logging techniques by investigating end-to-end guarantees of correctness, ensuring that solutions are verified relative to the original, human-understandable problem specification. This work has significant implications for debugging, auditability, and rigorous evaluation of algorithmic improvements. For further inspiration, candidates can explore the CertiFOX project ( CertiFOX ) and ZebraTutor explanations ( ZebraTutor ). Explanations are increasingly important for building trust in declarative solutions and complying with regulations such as GDPR, which require accountability in AI systems affecting human lives. The selected candidate may contribute by investigating explanations at various abstraction levels or exploring the relationship between explanations and proofs. Eligibility requires a MSc degree in computer science or a closely related field (e.g., mathematics) before the start date. Candidates should demonstrate interest in declarative problem solving, combinatorial optimization, knowledge representation, and logic-based methods. Strong scientific curiosity, good programming skills, and proficiency in English are essential. The offer includes a fully-funded PhD position for four years, with a scholarship competitive with Belgian salaries and a travel budget for conferences, workshops, and summer schools. The anticipated start date is autumn 2026, but this is negotiable. KU Leuven is committed to diversity, inclusion, and equal opportunity, fostering a respectful and socially safe environment for all. For more information, contact Prof. dr. Bart Bogaerts at [email protected] . Applications should be submitted online via the KU Leuven jobsite ( application link ) before the deadline of March 16, 2026.