I am currently a PhD student in Computer Science and Engineering in the Hong Kong University of Science and Technology (HKUST). I am proud to be co-advised by two great advisors, Amir Goharshady (now an associate professor in the University of Oxford) and Dimitris Papadopoulos. During my PhD, I was a visiting scholar at the University of Oxford. My research is generously supported by the Hong Kong PhD Fellowship Scheme (HKPFS). I am interested in the intersection of applied cryptography (especially on zkSNARKs and MPC), game theory and blockchains.

Before starting PhD, I was a MPhil in the Amir’s group during 2021~2023. Before coming to HKUST, I received my Bechalor’s degree in Automation from Tsinghua University in 2021.

I Am Beautiful

Publication

Check my Google scholar profile.

Note: My advisor Amir Goharshady adopts the convention from theoretical computer science to order authors in alphabetical order. This applies to all of my publications with ‘Goharshady, A.’.

2025

  • (IJCAI'2025) Barakbayeva, T., Cai, Z., Goharshady, A. & Keypoor K. Smart Contracts for Trustless Sampling of Correlated Equilibria.

2024

  • (ICBC'2024) Barakbayeva T., Cai, Z., & Goharshady, A. SRNG: An efficient decentralized approach for secret random number generation. hal

  • (ICBC'2024) Abidha V., Barakbayeva T., Cai, Z., & Goharshady, A. Gas-efficient decentralized random beacons. hal

2023

  • (ICBC'2023) Cai, Z., & Goharshady, A. Trustless and bias-resistant game-theoretic distributed randomness. paper hal

  • (MARBLE'2023) Cai, Z., & Goharshady, A. Game-theoretic Randomness for Proof-of-Stake. paper hal

  • (OOPSLA'2023) Cai, Z., Farokhnia, S., Goharshady, A., & Hitarth, S. Asparagus: Automated Synthesis of Parametric Gas Upper-Bounds for Smart Contracts. paper code

  • (IEEE Blockchain'2023) Ballweg, J., Cai, Z., & Goharshady, A. PureLottery: Fair Leader Election Without Decentralized Random Number Generation. hal code

2021

  • (ACL'2021) He, X.*, Cai, Z.*, Wei, W., Zhang, Y., Mou, L., Xing, E., & Xie, P. Towards Visual Question Answering on Pathology Images. ACL

Miscellaneous Experience

Academic Service

  • I served on the program committee of MARBLE'2025.

Research Directions

Zero-knowledge proofs and SNARKs

Blockchain and Distributed Systems

Formal Analysis of Distributed Systems

Economics of Blockchain

Static Program Analysis in Blockchain Smart Contracts