I am a third-year PhD student in computer science at the University of Toronto, advised by Ningning Xie. My research interests are in programming languages, types, and type inference in particular.
I did my master's under the supervision of Lionel Parreaux at HKUST, where I worked on type-safe and modular programming with mixins, and type inference for first-class polymorphism. Before that, I worked with Bruno Oliveira as a research intern. I received my bachelor's degree in computer science from Zhejiang University.
News
- Jun 2026 New paper accepted at OOPSLA'26.
- Jan 2026 Ningning gave a talk on formalizing type inference techniques at WITS'26.
- Jun 2025 Our PLDI'25 paper got a Distinguished Paper award!
- May 2025 Talked about Traits with Extensible Variants at ONPLS'25.
- Apr 2025 New paper accepted at PLDI'25.
- more
Publications
-
Modular Type Safety for Traits with Extensible Variants and Deep Pattern Matching
Andong Fan, Lionel Parreaux, Ningning Xie
OOPSLA 2026
paper -
Practical Type Inference with Levels
Andong Fan, Han Xu, Ningning Xie
PLDI 2025
paper / appendix / artifact
ACM SIGPLAN Distinguished Paper -
When Subtyping Constraints Liberate: A Novel Type Inference Approach for First-Class Polymorphism
Lionel Parreaux, Aleksander Boruch-Gruszecki, Andong Fan, Chun Yin Chau
POPL 2024
paper / technical report / demo / artifact -
super-charging Object-Oriented Programming through Precise Typing of Open Recursion
Andong Fan, Lionel Parreaux
ECOOP 2023
paper / extended paper / demo / artifact
Distinguished Artifact [news] -
A Calculus with Recursive Types, Record Concatenation and Subtyping
Yaoda Zhou, Bruno C. d. S. Oliveira, Andong Fan
APLAS 2022
paper / artifact -
Direct Foundations for Compositional Programming
Andong Fan*, Xuejing Huang*, Han Xu, Yaozhu Sun, Bruno C. d. S. Oliveira (*equal contribution)
ECOOP 2022
paper / extended paper / demo / artifact
Talk & Abstract
-
Type Inference Techniques: Implementation and Formalization, Better Together
Ningning Xie, Andong Fan
WITS 2026
abstract -
Simple Extensible Programming Through Precisely-Typed Open Recursion
Andong Fan
SPLASH 2022 Student Research Competition
abstract
Thesis
-
Modular Programming through Precise Typing of Open Recursion
Andong Fan
Master of Philosophy, HKUST, 2024
thesis
Awards
- The Fahiem Bacchus Memorial Graduate Student Scholarship, 2026
- ACM SIGPLAN Distinguished Paper Award, PLDI 2025
- Wolfond Fellowship, 2024
- Distinguished Artifact, ECOOP 2023
Teaching
- Teaching Assistant of Principles of Programming Languages (CSC324), University of Toronto, Fall 2026 & 2025 & 2024
- Teaching Assistant of Parallel Programming (CSC367), University of Toronto, Winter 2026
- Teaching Assistant of Data Structures and Analysis (CSC263), University of Toronto, Winter 2025
- Teaching Assistant of Principles of Programming Languages (COMP3031), HKUST, Fall 2023
Service
- Subreview: POPL 2027, PLDI 2025, SPLASH 2022 SRC
- Artifact Evaluation: PLDI 2025, POPL 2025, PLDI 2024, POPL 2024
- Student Volunteer: ECOOP 2023, SPLASH 2022
Misc
Subtlety and mystery intrigue me. Outside of research, I spend time immersing myself in films, J-pop and rock, and video games that share those qualities.
I watched and loved Ryusuke Hamaguchi's All of a Sudden (at TIFF'26!), Drive My Car, and Wheel of Fortune and Fantasy. My favorite Japanese alt rock song is World's End Supernova by Quruli. I am also a big fan of Remedy's games. I have completed Control three times and Alan Wake 2 twice, and have been looking forward to playing Control 2 on my mac!