January 2026 – Present
Teaching Assistant — Video Game Programming (CSE4500)
Washington University in St. Louis
Supporting students in debugging assignments and understanding course concepts; evaluating homework submissions.
Xinshi Feng
Available Fall 2027
IBM · Git & GitHubIBM · HTML/CSS/JSIBM · Cloud ComputingIBM · Software Engineering
Background
I'm a double major in Computer Science and Mathematics at Washington University in St. Louis (McKelvey School of Engineering), graduating May 2026.
My current research focus is de Rham cohomology and smooth manifolds, working under the supervision of Professor Yanli Song. I find beauty in how abstract topology and differential geometry describe the shape of spaces.
I also have published work in evolutionary game theory — applying Q-learning to model how conditional cooperation emerges and evolves in populations, published in Physical Review E.
I'm looking for Math PhD programs and research internships starting Fall 2027, in pure mathematics, applied math, or theoretical machine learning.
Teaching & Leadership
January 2025 – December 2025
Teaching Assistant — Introduction to Machine Learning (CSE417T)
Washington University in St. Louis
Weekly office hours, grading, and feedback for the introductory Machine Learning course.
January 2025 – May 2025
Grader — Optimization (ESE415)
Washington University in St. Louis
Graded homework assignments and addressed student inquiries for the graduate-level Optimization course.
January 2024 – May 2025
Teaching Assistant — Data Structures and Algorithms (CSE247)
Washington University in St. Louis
Held office hours 3x/week and supported studio sessions for Data Structures and Algorithms.
January 2024 – December 2024
Teaching Assistant — Data Structures and Algorithms Seminar (CSE247R)
Washington University in St. Louis
Delivered short lessons on classic algorithms and data structures not covered in the main curriculum.
Education
2023 – 2026
Washington University in St. Louis
McKelvey School of Engineering
Double Major in Computer Science and Mathematics
- ·Dean's List: Spring 2025, Fall 2024, Spring 2024, Fall 2023
2020 – 2023
Culver Academies
Culver, Indiana
High School Diploma
- ·Cum Laude (2022–2023)
- ·Honors in Computer Science (2022–2023)
- ·Blue Key (2021–2023)
- ·Honors in Mathematics (2021–2022)
Research
June 2025 – Present
de Rham Cohomology in Manifold Theory
Washington University in St. Louis
Studying smooth manifolds and de Rham cohomology under Prof. Yanli Song, computing classical examples via Mayer–Vietoris sequences.
July 2023 – February 2025
Evolution of Cooperation in a Bimodal Mixture of Conditional Cooperators
Remote Research Collaboration
Co-authored paper in Physical Review E modeling adaptive cooperation via Q-learning, investigating phase transitions in evolutionary game theory.
arXiv PaperJuly 2022 – February 2023
Incorporating Power Dynamic in Cooperation and Defection with Reinforcement Learning
Culver Academies
Used Q-Table reinforcement learning to study how social hierarchy affects cooperation dynamics.
July 2021 – February 2022
Letter Recognition with SVC, Random Forest and CNN
Culver Academies
Built ML models (SVM, Random Forest, CNN) to classify alphabetical characters and digitize historical documents.
Proficiency
Programming Languages
Python92%
Java85%
C / C++75%
JavaScript / HTML / CSS72%
Swift60%
Machine Learning & AI
Reinforcement Learning88%
Convolutional Neural Networks80%
Support Vector Machines82%
Random Forests83%
Computer Vision75%
Mathematics
Differential Topology80%
Linear Algebra90%
Optimization82%
Probability & Statistics88%
Tools & Platforms
Git / GitHub85%
Microsoft Office90%
LaTeX70%
“Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.”
— William Paul Thurston
Outside the Classroom
Mathematics
Fascinated by pure mathematics — topology, analysis, and abstract algebra outside of coursework.
Coffee & Study Culture
A firm believer in good coffee and deep focus sessions. Always on the lookout for the best study spots.
Fitness
Regular gym-goer who believes physical discipline and mental discipline are closely connected.
Music
Enjoys listening to and exploring music across genres as a way to decompress after intense study sessions.
Let's Connect