07/25/25: RefinedC: Automating the Foundational Verification of C Code with Refined Ownership Types with Michael Sammler

Mingwei Zhenga Ph.D. candidate in the Department of Computer Science at Purdue University, advised by Prof. Xiangyu Zhang since 2021. Before that, she received her Bachelor’s degree in Computer Science and Technology from Huazhong University of Science and Technology in 2020. Mingwei's research lies at the intersection of Large Language Models (LLMs) and Software Engineering. She builds LLM agents that combine program analysis with LLMs for deep codebase understanding that improve software correctness, robustness, and trustworthiness. Today Mingwei joined us to discuss some ongoing work which she previously presented at IEEE Security and Privacy LangSec, applying language models to bug detection in protocols with IETF RFCs. This was a great talk with deep, technical content and a good conversation. We hope you enjoy!

Today Kaiyu Yang from Meta joined us to discuss formal reasoning using LLMs, particularly in the context of interactive theorem provers.  This is a really fast-moving and exciting field in which reinforcement learning and theorem proving combine to provide a new frontier for fully automated reasoning, and Kaiyu is at the bleeding edge of it.  We were really lucky to get an hour of Kaiyu's time and we hope you enjoy the talk as much as we did!

Michael Sammlern assistant professor leading the Programming Languages and Verification Group at the Institute of Science and Technology Austria (ISTA). Today he joined us to talk about his three primary projects: RefinedC, which uses a refinement and ownership type system to verify C code, Islaris, which shows how to scale verification of assembly code to realistic models of real-world architectures, and DimSum, which provides a decentralized approach for reasoning about multi-language programs (with a particular focus on RefinedC). We had a small but really dedicated crowd which facilitated an excellent discussion. This was a really fun one and we hope you enjoy it as much as we did!

Dimitri Mitropoulos is a Michigan-based typescript dev, linguist, and classicist who joined us to talk about his completely unhinged, odyssean, and frankly just unwise project to get DOOM running completely within Typescript's type system. Someone give the dude a PhD, please.

Jenna DiVincenzo is an Assistant Professor in the Elmore Family School of Electrical and Computer Engineering @ Purdue University. She is broadly interested in research spanning software verification, programming languages, and software engineering, especially research aimed at making verification techniques and programming languages more usable and scalable. Today Jenna joined us to talk about her broad research program in gradual verification. This was a really interesting talk with great Q&A and we hope you enjoy it as much as we did!

Prashant Anantharaman is a long-time BCC group member and has presented as both a solo researcher and a panelist to prior events. Today he joined us to present some of his work with NARF, to appear at IEEE S&P, on generating grammars for fuzzing using LLMs. This is a super exciting new frontier for LLMs and LangSec generally and his talk was wonderful.

Ramit Das is a formal verification engineer at Intel and an avid Boston Computation Club group member. Ramit and I have been speaking for ages about formal methods, exchanging papers, etc. and today he finally agreed to come give a talk to the group about his area of expertise -- descriptive complexity. This was a really fun talk and an excellent introduction for anyone looking to get their feet wet with complexity theory, some language theory, and even a smidgeon of model theory and underpinnings of abstract interpretation. It was really fun and we can't wait to host another talk by Ramit sometime in the future!

Today Marc Denecker joined us to present How and Why to extend First Order Logic for Knowledge-Based Systems. This presentation provided the setup for a follow-on that Marc's student Simon Vandevelde is set to give on IDP-Z3, a formal reasoning machine that Marc and Simon have built. This was a really interesting talk touching on a variety of forms for formal logic, decision procedures, and industrial use-cases thereof, potentially with profound implications for the future and realizability of so-called AGI.

Today Daniel Melcer joined us to present Constrained Decoding for Code Language Models via Efficient Left and Right Quotienting of Context-Sensitive Grammars (https://arxiv.org/pdf/2402.17988). This is work he completed while at Amazon, and it's a really interesting project around how to constrain, guide, and check language models such that they generate valid code within a given context. We really appreciate that Daniel took the time to talk to us and hope you like the talk as much as we did!

Michael H. Borkowski is an Assistant Professor of Practice in the Department of Computer Science at Purdue University. Before joining Purdue, he earned his Ph.D. from the Department of Computer Science and Engineering at UC San Diego, where he was affiliated with the ProgSys Group. Today Michael joined us to discuss LiquidHaskell, a very cool project that incorporates a kind of refinement types, with SMT-based proofs, into Haskell. This was a really compelling talk and we hope you enjoy it as much as we did!