I am Congying (Alex) XU, a final year PhD student at HKUST, supervised by Chair Prof. Shing-Chi CHEUNG (IEEE Fellow), and a visiting scholar at CMU (Carnegie Mellon University), collaborating with Prof. Christian Kästner. I am exploring research topics about LLM-Empowered Software Engineering and Trustworthy AI Systems.

🔥 News

• ✨ I am officially on the job market (2026), seeking positions of Research Scientist (Industry) or PostDoc Researcher(Academia). 
  Here is my [CV]. If you know of a postion that might be a match, or would like to hear more about my work, please feel free to reach out (📧: congying.xu@connect.ust.hk)!

• 2026.01: 🎉 Two papers “Can Emulating Semantic Translation Help LLMs with CodeTranslation? A Study Based on Pseudocode” [Paper], and “Less Is More: Failing Test Generation with Large Language Models” have been accepted by TOSEM 2026!

• 2025.12: 🎉 One paper “Towards Verifiably Safe Tool Use for LLM Agents” has been accepted by ICSE-NIER 2026!

📝 Projects and Publications

LLM Agent Safety and Reliability

• ICSE-NIER 2026 Towards Verifiably Safe Tool Use for LLM Agents [To appear]
  Aarya Doshi, Yining Hong, Congying Xu, Eunsuk Kang, Alexandros Kapravelos, Christian Kästner

LLM-Empowered Software Testing

• ASE 2024 MR-Adopt: Automatic Deduction of Input Transformation Function for Metamorphic Testing [Paper]
  Congying Xu, Songqiang Chen, Jiarong Wu, Shing-Chi Cheung, Valerio Terragni, Hengcheng Zhu, Jialun Cao

• TOSEM 2024 MR-Scout: Automated Synthesis of Metamorphic Relations from Existing Test Cases [Paper]
  Congying Xu, Valerio Terragni, Hengcheng Zhu, Jiarong Wu, Shing-Chi Cheung

• TOSEM 2026 Less Is More: Failing Test Generation with Large Language Models [To Appear]
  Tsz-On Li, Xiaochuan Yan, Wenxi Zong, Yibo Wang, Haoye Tian, Congying Xu, Ying Wang, Shing-Chi Cheung, and Jeff Kramer

LLM-Empowered Code Translation and Generation

• TOSEM 2026 On Effective Semantic Translation for Code: A Study Based on Pseudocode [Paper]
  Songqiang Chen, Congying Xu, Jingyi Chen, Jialun Cao, Jiarong Wu, Shing-Chi Cheung

• TSE 2025 Question Selection for Multi-Modal Code Search Synthesis using Probabilistic Version Spaces [Paper]
  Jiarong Wu, Yanyan Jiang, Lili Wei, Congying Xu, Shing-Chi Cheung, Chang Xu

Software Supply Chain Security

• FSE 2022 Tracking Patches for Open Source Software Vulnerabilities [Paper]
  Congying Xu, Bihuan Chen, Chenhao Lu, Kaifeng Huang, Xin Peng, Yang Liu

• EMSE 2022 Characterizing usages, updates and risks of third-party libraries in Java projects [Paper]
  Kaifeng Huang, Bihuan Chen, Congying Xu, Ying Wang, Bowen Shi, Xin Peng, Yijian Wu, Yang Liu

• 🏆 ICSME 2020 An Empirical Study of Usages, Updates and Risks of Third-Party Libraries in Java Projects. [Paper]
  Ying Wang, Bihuan Chen, Kaifeng Huang, Bowen Shi, Congying Xu, Xin Peng, Yijian Wu, Yang Liu

• FSE 2020 Interactive, Effort-aware Library Version Harmonization [Paper]
  Kaifeng Huang, Bihuan Chen, Bowen Shi, Ying Wang, Congying Xu, Xin Peng

Recommendation System

• ICSE 2019 MULAPI: A Tool for API Method and Usage Location Recommendation [Paper]
  Congying Xu, Bosen Min, Xiaobing Sun, Jiajun Hu, Bin Li, Yucong Duan

• JSS 2018 MULAPI: Improving API method recommendation with API usage location [Paper]
  Congying Xu, Xiaobing Sun, Bin Li, Xintong Lu, Hongjing Guo,

Invited Talks

• 2025.12, Foundations of Software Testing in APSEC 2025, Macao SAR.

🤝 Service

• Reviewer: AE@ICSE 2026, TOSEM 2025, ASEJ 2025, AE@ISSRE 2024, AE@ISSRE 2023
• Shadow-Reviewer: FSE 2025, ASE 2025, ISSTA 2025
• Volunteer: FSE 2025, ASE 2021

🎖 Honors and Awards

• 2025, Overseas Research Award, HKUST.
• 2022.09 - now, Postgraduate Studentship (PGS), HKUST.
• 2019, National Scholarship, Ministry of Education of China.
• 2019, Outstanding Graduates of Yangzhou University.
• 2018, First Prize·Blue Bridge Cup National Programming Competition, Jiangsu (Java).
• 2014, First Prize·Chemistry Olympiad Contest, Jiangsu Province.

📖 Educations

• 2022.09 - now, PhD Student, The Hong Kong University of Science and Technology.
• 2025.01 - 2025.06, Visiting Scholar, Carnegie Mellon University.
• 2019.09 - 2022.06, Master Degree, Fudan University.
• 2015.09 - 2019.06, Bachelor Degree, Yangzhou University.

📖 Teaching Experience

• COMP4633 Competitive Programming in Cybersecurity (Fall 2025–26)
• COMP3021 Java Programming (Fall 2024–25)
• COMP1021 Introduction to Computer Science (Python Programming) (Fall 2023-24)

Schedule a Meeting

I’d be happy to connect! Please book a time via my calendar 👈.