Konstantinos Kallas

Overview

I am an assistant professor of computer science at UCLA. My research interests lie in the intersection of computer systems, compilers, and programming languages. I work with some amazing students in the Programmable Software Systems Lab.

Looking for students: I am looking for motivated students to work with me on problems in computer systems, compilers, and programming languages. If you are interested in the style of research that I am doing, read this and send me an email :)

Shell Analysis Tutorial at POPL 2026: Together with Michael Greenberg and Nikos Vasilakis we are organizing a tutorial on analyzing shell scripts at POPL 2026. If you are at POPL drop by to learn how you can do PL and Systems research on the shell! (Link)

Links: Research, Group, Teaching, Bio, Papers, Software, Projects, Service and Outreach, Misc

Research

The goal of my research is to enable the development of high-performance applications with robust correctness guarantees. To achieve this goal, I build practical programmable software systems that target realistic workloads in widely-used environments. I build my systems on solid foundations using techniques drawn from the programming languages, compilers, and formal methods literature.

Here are some of my recent papers. A complete list of my publications, talks, reports, and software can be found here or on my Google Scholar profile.

Cloud Software Systems

• Rajomon: Decentralized and Coordinated Overload Control for Latency-Sensitive Microservices (NSDI 25, pennsail/rajomon Star)
• Netherite: efficient execution of serverless workflows (Best of VLDB 22)
• MuCache: a General Framework for Caching in Microservice Graphs (NSDI 24, eniac/mucache Star)
• Executing Microservice Applications on Serverless, Correctly (POPL 23, eniac/mu2sls Star)
• Netherite: Efficient Execution of Serverless Workflows (VLDB 22, microsoft/durabletask-netherite Star)
• Durable Functions: Semantics for Stateful Serverless (OOPSLA 21)

Compilers and Systems for Shell Scripts

• The Koala Benchmarks for the Shell: Characterization and Implications (USENIX ATC 25, kbensh/koala Star)⭐ Best Paper Award ⭐
• From Ahead-of- to Just-in-Time and Back Again: Static Analysis for Unix Shell Programs (HotOS 25)
• Executing Shell Scripts in the Wrong Order, Correctly (HotOS 23)
• DiSh: Dynamic Shell-Script Distribution (NSDI 23, binpash/dish Star)
• Practically Correct, Just-in-Time Shell Script Parallelization (OSDI 22, binpash/pash Star)
• An Order-aware Dataflow Model for Parallel Unix Pipelines (ICFP 21)
• Unix Shell Programming: The Next 50 Years (HotOS 21, video)⭐ Distinguished Presentation Award ⭐
• PaSh: Light-touch Data-Parallel Shell Processing (EuroSys 21, binpash/pash Star)⭐ Best Paper Award ⭐

Teaching

• (Fall 2025) CS 239: Topics in the intersection of systems and programming languages (Website)
• (Spring 2025) CS 134: Distributed Systems (Website)
• (Winter 2025) CS 239: Cloud Software Systems (Website)

Software

I am interested in doing research that leads to usable open-source systems. As an example, my research has led to the development of the PaSh project, a software ecosystem that is supported by the Linux Foundation and has a lively open-source community.

Here are some example systems that have come out of my group's research. A complete list can be found here.

• PaSh (Github) Star
  A system that automatically parallelizes your shell scripts. Hosted by the Linux Foundation.
• try (Github) Star
  A tool that lets you run a command and inspect its effects before committing them to your system.
• mucache (GitHub) Star
  A system that automatically adds and manages caches in microservice applications.

Personal

In my free time I enjoy human activities, like reading books. I really like lying down and falling asleep in nature, with or without the presence of other people. My magnum opus is editing this video and producing its thumbnail. I occasionally like producing rhythmic sounds from electric guitars, usually in the context of some jam session.