Rachel Zeng

Projects

Things I've built

Selected work across systems, software engineering, and data analysis.

Systems

Fault-tolerant Key-value Service

Jan 2023 – May 2024

C++
Distributed

Distributed key-value store with replication across multiple servers, crash recovery, and concurrent client handling. Detailed design decisions and optimizations in documentation.

Key-value Database System

Sept – Dec 2023

C++
Storage

Multi-stage database with in-memory structures and persistent storage. Buffer pools with LRU eviction, static B-Trees, and an LSM-tree with Bloom filters to reduce disk I/O.

Parallel Memory Allocator

C
Concurrency

A parallel memory allocator focused on speed, scalability, false-sharing avoidance, and minimal fragmentation. Includes design and performance evaluations.

Software Engineering

Telemedicine for Stroke Rehabilitation

Sept 2024 – May 2025

AR
React
Unity

User-oriented system that helps clinicians design rehabilitation curriculums tailored to individual patients — placing virtual objects in the patient's living areas to define tasks without code.

Personal Writing Assistant (Rightee)

AI
TypeScript

A writing assistant that suggests improvements while preserving the writer's voice — instead of fully rewriting content with overly fancy AI-generated prose.

Moba Tracker Web App

React
Node.js
MongoDB

Web app with user registration, admin governance, profile management, interactive forums, and game performance tracking with stats on win rates and champion usage.

Data Analysis

Product Performance Analysis

R
Statistics

Investigated MINGAR's Fitness Tracker product line and potential wearable device deficiencies.

College Admissions Analysis

R
Statistics

Examined factors influencing variation in admission rates across U.S. colleges and universities.

MLS Player Annual Earnings

R
Regression

Linear regression model relating MLS player earnings to performance — useful for clubs estimating value and players targeting earnings growth.

Factorial Experiment of CPU Usage

R
Experimental design

Identified specific tasks that drive high CPU usage to help prevent slowdowns and crashes.

Models & Algorithms for Social Networks

Sept 2021 – Dec 2022

Python
Twitter
ROP

Designed six utility functions and applied them to 80,000+ users and 12.7M tweets, expanding online communities through new algorithms. Presented at the 2022 ROP Fair.