Date: November 13, 2026
Speaker: Nikos Vasilakis, Assistant Professor of Computer Science, Brown University
Title: Interacting with Shell Programs, Confidently
Host: Rachee Singh
Abstract: Shell programs are a pervasive substrate for system administration, automation, and software development—whether invoked directly or indirectly through AI agents, build systems, Dockerfiles, and other wrappers. Unfortunately, they are prone to subtle, severe, and often irreversible effects. In this talk, I will present a series of systems that, for the first time, enable significantly higher confidence in shell-script interaction. Rt is a novel overlay type system built around regular languages for expressing, propagating, and checking constraints over the values of interprocess communication streams, files, and the commands operating on them. Sash is a new static-analysis system automatically detecting catastrophic bugs deep in shell programs, using effect-oriented symbolic execution. And Try is a higher-order abstraction and corresponding subsystem for inspecting, controlling, and manipulating the effects of black-box commands during and after their execution. Combined, these systems allow developers, users, AI agents, and other systems that rely on shell programs to catch disasters well before they occur.
Bio: Nikos Vasilakis is on the faculty of the Computer Science Department at Brown University, where he co-directs the Brown Systems group. His research includes software systems, programming languages, and computer security—and has been recognized by a Google Junior Faculty award, an Amazon Research award, an NSF CAREER award, and best-paper awards at SOSP'26, OSDI'26, ATC'25, AsiaCCS'23, FSE'21, EuroSys'21, and more. His current focus is on automatically transforming systems to add new capabilities such as bolt-on reliability, scaleout, incrementalization, and security against a variety of threat models. More: nikos.vasilak.is & atlas.cs.brown.edu.
