I’m currently pursuing a PhD in distributed systems, co-advised by Joe Hellerstein and Natacha Crooks in the Sky Computing Lab. I’m excited about automating what we find hardest about distributed systems: creating new protocols.
Instead of creating individual bespoke protocols from scratch, I believe we should:

1. Automatically optimize distributed protocols. Traditionally, depending on the performance requirements, entirely new protocols would be created from scratch, requiring expertise and often resulting in correctness errors. We should instead take existing, well-studied protocols, like Paxos, and optimize them automatically using a set of small, provably-correct rewrites. This is my goal with Hydro.
2. Automatically provide programs with resistance to rollback attacks, a form of attack that programs running on TEEs (Trusted Execution Environments, like Intel SGX) are vulnerable to. Traditionally, new implementations of databases and replication protocols would be created from scratch to address rollback attacks. We should instead provide a simple lift-and-shift experience to developers moving their applications to TEEs. This is my goal with Rollbaccine.

In my spare time, I love playing badminton, teaching, and listening to classical music. Here’s a video of my senior recital at Cornell, where I performed Brahms Ballades Op. 10, Thomas Ades’ Darknesse Visible, and Beethoven’s Appassionata Op. 57, one of my favorite sonatas.

Publications

Rollbaccine: Herd Immunity Against Rollbacks for TEEs (WIP)
Video / Poster / Github
David Chu, Soujanya Ponnapalli, Chris Liu, Eddy Ashton, Amaury Chamayou, Natacha Crooks, Heidi Howard
Presented at ACM SOSP 2023 Poster Session

Bigger, not Badder: Safely Scaling BFT Protocols
Github
David Chu, Chris Liu, Natacha Crooks, Joe Hellerstein, & Heidi Howard
PaPoC 2024

Optimizing Distributed Protocols with Query Rewrites
Video / Github / Technical Report
David Chu, Rithvik Panchapakesan, Shadaj Laddad, Lucky Katahanas, Chris Liu, Kaushik Shivakumar, Natacha Crooks, Joe Hellerstein, & Heidi Howard
ACM SOSP 2021 Student Research Competition (Winner)
SIGMOD 2024

Take Out the TraChe: Maximizing (Tra)nsactional Ca(che) Hit Rate
Audrey Cheng, David Chu, Terrance Li, Jason Chan, Natacha Crooks, Joseph M. Hellerstein, Ion Stoica, & Xiangyao Yu
OSDI 2023

Scalog: Seamless Reconfiguration and Total Order in a Scalable Shared Log
Cong Ding, David Chu, Evan Zhao, Xiang Li, Lorenzo Alvisi, & Robbert Van Renesse
NSDI 2020

Reliable, Efficient Recovery for Complex Services with Replicated Subsystems
Free link
Edward Tremel, Sagar Jha, Weijia Song, David Chu, & Ken Birman
DSN 2020

Media Coverage

9/20/24 Blog post from Murat Demirbas on my HPTS gong show talk (at the end of the article). Thanks Murat!
6/28/24 Blog post from Murat Demirbas on our SIGMOD 24 paper: Optimizing Distributed Protocols with Query Rewrites

Research Activity

2025

1/7 I was awarded the RDI Frontier Fellows Award!

2024

11/14 Invited talk at Northeastern
11/13 Invited talk at Brown
11/12 Invited talk at MIT
9/16 My talk on Yu-Gi-Oh! and (Optimizing Distributed Protocols with Query Rewrites) was voted the best gong show talk at HPTS!
7/10 Poster presentation: Ongoing work after (Optimizing Distributed Protocols with Query Rewrites) at OSDI 2024
6/13 Paper presentation: (Optimizing Distributed Protocols with Query Rewrites) at SIGMOD 2024
4/22 Paper presentation: (Bigger, not Badder: Safely Scaling BFT Protocols) at PaPoC 2024 (EuroSys)
3/20 Invited talk: (Rollbaccine: Herd Immunity Against Rollbacks for TEEs) at Intel
3/11 Acceptance: (Bigger, not Badder: Safely Scaling BFT Protocols) will be published at PaPoC 2024

2023

9/28 Poster presentation: (Rollbaccine: Herd Immunity Against Rollbacks for TEEs) at SOSP 2023
9/20 Acceptance: (Optimizing Distributed Protocols with Query Rewrites) will be published at SIGMOD 2024 with minor revisions

Awards

2025 RDI Frontier Fellows Award
2024 HPTS Best Gong Show Talk
2024 UC Berkeley EECS Evergreen Award for Undergraduate Researcher Mentoring
2023 UC Berkeley EECS Award for Undergraduate Researcher Mentoring
2023 UC Berkeley SRC-URO Award
2022 UC Berkeley SRC-URO Award
2021 UC Berkeley SRC-URO Award
2021 ACM SOSP Student Research Competition Winner

Service

2024 SIGMOD ARI Reviewer

Extra-Curricular Projects

Cornell Design & Tech Initiative

DTI was a project team focused on using technology to generate community impact. We curated events to educate students on web and mobile technologies; at the same time, we worked as a team to design apps and websites with the goal of student support. My proudest achievement is the establishment of biweekly DevSeshes and onboarding sessions for developers on the team, in which I taught developers on the team upcoming technologies such as React, Firebase, and Android/iOS programming.

Here are some projects I’ve worked on as part of the team.

CUEvents cue eve

Frontend & Backend / iOS / Android
A platform to gather all events on campus. I was a front-end developer, then product manager on this subteam. I’ve helped program all aspects of the app, including its Android (Java), iOS (Swift), backend (Django), and frontend (React) components. It’s currently in beta.

Cornell Orientation

Backend / iOS / Android
An app to provide students with personalized events for orientation week based on the college they’re enrolled in, with built-in search, filters, and directions. I created the Android (Java) and iOS (Swift) portions of the app, as well as rewriting the backend from Django to Firebase.

Personal projects

And My Code Is Ended

Android / Backend
An app to wake the user up with a line of code. If you’re tired of constantly checking when your code is finished, add that line of code to your script, go to sleep, and be woken up by the app!

Visit Once

Source
A chrome extension that limits selected websites to a single visit a day, created to maximize productivity.

NSHS Guide

Frontend & Backend / iOS / Android
An iOS, Android app + website for students at Newton South High School to check which classes they can skip for that day. It’s integrated into each students’ daily schedule so they are each alerted which of their teachers are absent. The app read emails sent by the principal’s secretary, parsed it with PHP, stored the data in MySQL, and beamed messages to users detailing their updated schedule. I was the sole Android and iOS developer on the app, working with Eric Lin, the backend developer. I also rewrote the backend in PHP and frontend in Polymer.js, pushed by Google as an Angular alternative at the time.

Froggy Math

iOS
An iOS app to help my fiance drill mental math skills.

It’s time to [insert your thing]

Website / Source
A website to create your custom “It’s time to duel” sound.