We invite applications for a fully funded PhD position at the University of Tartu, Estonia, in the area of logic in computer science, database theory, and semiring semantics. The research explores how classical logical and complexity-theoretic tools can be extended to models and computations enriched with semirings—a framework underlying annotated databases, provenance, confidence scoring, and related applications. Requirements: Master’s degree in computer science, mathematics, or a related field; background and interest in logic, theoretical computer science, or database theory. Opportunities: Work in the modern Delta Centre, home to the University of Tartu's Institute of Computer Science. The position offers local and international collaboration possibilities—including a planned extended research visit to the University of Helsinki—and participation in research seminars within the institute. * Gross salary: €2200–2300/month * Application period: 1–15 May 2025 * Application portal: https://estonia.dreamapply.com/en_GB/courses/course/1189-phd-mathematics-and... * Admission info: https://ut.ee/en/curriculum/mathematics-and-computer-science * Open calls (see Computer Science #7): https://ut.ee/en/content/phd-open-calls For informal inquiries, contact Miika Hannula (miika.hannula@ut.ee).