Josh Fried

I am an Assistant Professor in the Department of Computer and Information Science at the University of Pennsylvania. I completed my PhD at MIT CSAIL, where I was advised by Adam Belay. My undergraduate degree is also from Penn, where I researched applied cryptography and systems security with Nadia Heninger.

Before joining Penn, I spent a year as a Software Engineer at Google working on datacenter networking.

My research aims to improve datacenter efficiency by designing innovative operating systems and resource management techniques that leverage kernel bypass, microsecond-scale scheduling, and system-level optimizations to achieve significant performance and efficiency gains. Much of this work culminated in Junction, which brings the efficiencies of these designs to unmodified applications.

Teaching

CIS 7000: Operating Systems for Datacenters — Fall 2026

Research Group

At Penn, I lead a research group focused on next-generation datacenter software systems. We study how modern hardware and software interact, and develop new abstractions, scheduling models, and control mechanisms that improve performance, efficiency, and adaptability at scale.

I am looking for PhD students who are passionate about building and understanding real systems, and who are excited to explore new ideas that push the boundaries of datacenter computing. If you’re interested in joining my group, please apply here.