Stephanie Weirich Named 2025 ACM Fellow

Stephanie Weirich, ENIAC President’s Distinguished Professor in Computer and Information Science, has been named a 2025 Fellow of the Association for Computing Machinery (ACM), the world’s preeminent educational and scientific computing society.

Selected by their peers for achieving remarkable results through their technical innovations and service to the field, ACM Fellows represent the top one percent of ACM’s global membership. This year, ACM named 71 new Fellows from 14 countries, drawn from a worldwide community of more than 100,000 computing professionals.

Weirich is being recognized for “contributions to static type systems and mechanized mathematics of programming languages.” Her research has played a foundational role in advancing the theory and practice of programming languages, with work spanning advanced type systems, dependently typed programming, compiler design and formal methods that improve the reliability and security of software systems. In addition to her research contributions, Weirich is widely recognized for her service and leadership within the programming languages community.

“I’m deeply honored to be part of the ACM Fellow Class of 2025,” says Weirich. “I am fortunate to have contributed to the design of the Haskell programming language and to the use of mathematical proof assistants for machine-checked reasoning about programming language meta theory. I’m grateful to my colleagues, students and mentors, both at Penn Engineering and in the ACM SIGPLAN community, who have made this work possible.”

A member of the Penn Engineering faculty since 2003, Weirich is part of the Department of Computer and Information Science and the Programming Language Club research group. She has held numerous leadership roles in the international computing community, including service on conference steering committees, editorial boards and professional organizations. She is also deeply committed to mentoring students and early-career researchers and to broadening participation in computing.

The 2025 ACM Fellows work at leading universities, corporations and research institutions across the globe and are recognized for contributions in a wide range of computing research areas, including artificial intelligence for healthcare, computer graphics, data management, human-computer interaction, mobile computing, robotics, security, sustainability and more.

“These men and women represent the top 1% of professionals in our association,” says ACM President Yannis Ioannidis. “As we congratulate the new Fellows for their accomplishments, we hope that their work will also serve as an inspiration to the next generation.”

Read the full list of 2025 ACM Fellows here and learn more about Weirich’s research on her website.