Sebastian Angel

Associate Professor and Chair of Undergraduate Curriculum

Department of Computer and Information Science

University of Pennsylvania

Amy Gutmann Hall, Office 325

3333 Chestnut Street

Philadelphia, PA 19104

Email: sebastian.angel at cis.upenn.edu

Phone: +1 (215) 898-9252

I'm an associate professor and the undergraduate curriculum chair of the Computer and Information Science department at Penn. My research group is part of the Distributed Systems Laboratory, the Security and Privacy Laboratory, and The Warren Center for Network and Data Sciences. I'm the recipient of an NSF CAREER Award, a JPMorgan Faculty Award, the ACM SIGOPS Dennis M. Ritchie Dissertation Award, and the Bert Kay Best Dissertation Award. I was previously at Microsoft Research.

I'm broadly interested in systems, security, privacy, and networking. My work aims to:

Build new privacy-preserving systems, from messasing apps to online advertising.
Bring accountability to online services by forcing these services to prove that they are doing the right thing.
Provide strong consistency and fault tolerance for large scale distributed systems at low cost.
Design the next generation of operating systems. See the LDOS project page.

Courses (Fall 2025)

Research Group (see alumni)

PhD students

Masters students

Undergraduate students

Conference Organization

2026: S&P
2025: OSDI, SOSP, Latincrypt
2024: SOSP, Workshop in PIR
2023: OSDI, S&P
2022: S&P
2021: HotOS (general chair), SOSP, OSDI, PETS, EuroSys, USENIX Security
2020: OSDI, PETS, ICDCS, WPES
2019: HotOS, PETS

Recent publications (see all)

Quilt: Resource-aware Merging of Serverless Workflows

Yuxuan Zhang and Sebastian Angel

SOSP 2025 (to appear), Seoul, South Korea, October 2025. [abstract]

Structural temporal logic for mechanized program verification

Eleftherios Ioannidis, Yannick Zakowski, Steve Zdancewic, and Sebastian Angel

OOPSLA 2025, Singapore, October 2025. [abstract, paper, code]

CausalMesh: A Causal Cache for Stateful Serverless Computing

Haoran Zhang, Shuai Mu, Sebastian Angel, and Vincent Liu

PVLDB Volume 17, Issue 13, 2024.

To be presented at VLDB 2025, London, UK, September 2025. [abstract, paper, code]

ACM SIGMOD Research Highlights Award [perspective by Phil Bernstein]

VLDB 2024 Best paper award nominee

Mako: Speculative Distributed Transactions with Geo-Replication

Weihai Shen, Yang Cui, Siddhartha Sen, Sebastian Angel, and Shuai Mu

OSDI 2025, Boston, MA, July 2025. [abstract, paper, code]

Oryx: Private detection of cycles in federated graphs

Ke Zhong and Sebastian Angel

PETS 2025, Washington, DC, July 2025. [abstract, paper, code]

Reef: Fast Succinct Non-Interactive Zero-Knowledge Regex Proofs

Sebastian Angel, Eleftherios Ioannidis, Elizabeth Margolin, Srinath Setty, and Jess Woods

USENIX Security 2024, Philadelphia, PA, August 2024. [abstract, paper, code]

MuCache: A General Framework for Caching in Microservice Graphs

Haoran Zhang, Konstantinos Kallas, Spyros Pavlatos, Rajeev Alur, Sebastian Angel, and Vincent Liu

NSDI 2024, Santa Clara, CA, April 2024. [abstract, paper, code]

On a Foundation Model for Operating Systems

Divyanshu Saxena, Nihal Sharma, Donghyun Kim, Rohit Dwivedula, Jiayi Chen, Chenxi Yang, Sriram Ravula, Zichao Hu, Aditya Akella, Sebastian Angel, Joydeep Biswas, Swarat Chaudhuri, Isil Dillig, Alex Dimakis, Brighten P Godfrey, Daehyeok Kim, Christopher Rossbach, and Gang Wang

MLSys@NeurIPS, New Orleans, LA, December 2023. [abstract, paper]

Nimble: Rollback Protection for Confidential Cloud Services

Sebastian Angel, Aditya Basu, Weidong Cui, Trent Jaeger, Stella Lau, Srinath Setty, and Sudheesh Singanamalla

OSDI 2023, Boston, MA, July 2023. [abstract, paper, extended report, code]

Flamingo: Multi-Round Single-Server Secure Aggregation with Applications to Private Federated Learning

Yiping Ma, Jess Woods, Sebastian Angel, Antigoni Polychroniadou, and Tal Rabin

S&P 2023, San Francisco, CA, May 2023. [abstract, paper, extended report, code]

Addax: A fast, private, and accountable ad exchange infrastructure

Ke Zhong, Yiping Ma, Yifeng Mao, and Sebastian Angel

NSDI 2023, Boston, MA, April 2023. [abstract, paper, code]

Executing Microservice Applications on Serverless, Correctly

Konstantinos Kallas, Haoran Zhang, Rajeev Alur, Sebastian Angel, and Vincent Liu