Andrew Choi

About Me

I currently work as a Software Engineer at OnePay, building tools to help Americans achieve financial progress. I am broadly interested in software engineering, distributed systems, and blockchain.

Prior to this, I was a Software Engineer at Tulip creating low code app editors for front line operations, and at Algorand, where I worked on programmability, smart-contract languages, and developer infrastructure for Web3 apps.

Before industry, I was a graduate student at the University of Toronto's Department of Computer Science, where I worked with Prof. Fan Long. I worked summers at Google and Amazon where I worked in the Global Networking group, AWS DynamoDB, and IoT Core.

Outside of work, I like playing my trombone, throwing baseballs, and skimming books.

You can reach me by email or on LinkedIn if you'd like to talk!

Experience

OnePay

May 2025 - Present

Software Engineer

Working on the AI servicing team to develop financial tooling using LLM/RAGs (TypeScript, AWS, Terraform)

Tulip

Jan 2024 - Apr 2025

Software Engineer

Worked on improving the app building experience on Tulip (React, MongoDB, TypeScript)
Developed components to compare and "diff" Tulip apps to improve change management workflows in regulated industries.
Worked to standardize floating point calculations on the platform to better serve life science customers
Led efforts to improve code quality and decrease on-call load by improving existing test frameworks and performance tooling (Cypress, Docker, Jest, K6, Grafana)
Worked in a cross-collaborative tiger team to modernize our software architecture in the monorepo to reduce build complexity and improve code readability and testability.

Algorand

Jun 2021 - Nov 2023

Software Engineer ( @algochoi)

Worked on open-sourced go-algorand consensus protocols, compilers, tools, and infrastructure in Go for a $1Bn+ market cap blockchain, founded by Turing Award Cryptographer Silvio Micali
Designed and implemented parts of the AVM assembler and the PyTeal programming language to allow safer & better programmability for smart contracts
Developed features, integrated Cucumber tests, and maintained infrastructure in Docker and CircleCI for the Algorand Go/Java/Python/JS SDK
Introduced new AVM v6+ features (recursive inner contract calls) for the Algorand database indexer and Chrome Web debugger
Introduced OpenSearch telemetry services and developer infrastructure to Conduit (blockchain data streaming pipeline)
Reduced build and integration testing times by 60% by refactoring, optimizing, and using a dev-mode network in external-facing repos (Cucumber, Docker, CircleCI, Github Actions)
Presented live demos to developers in ecosystem: Featured on the Proof of State Show!

Google

Summer 2020

Software Engineer Intern

Worked on the Google Global Networking team to develop an OpenConfig service in Go to aggregate and stream networking information for vendor-neutral routers
Created a client that asynchronously streams events from the service using gNMI/gRPC APIs to log abnormal network activity

Amazon Web Services (AWS)

Summer 2018, 2019

Software Development Engineer Intern

Summer 2019
- Worked on the Amazon DynamoDB team to develop an EC2 host management tool for table indexing requests
- Created an internal Java client library for REST APIs to monitor and replace unhealthy hosts, reducing tickets to manually migrate stale instances
Summer 2018
- Worked on the AWS IoT team to streamline the on-boarding process for things and devices using the AWS Python SDK and IoT SDK

UCLA

Summer 2017

Research Student at the Statistical and Relational Artificial Intelligence Lab

Explored new ways to perform faster inference on Bayesian Networks by compiling networks into hardware and optimizing graph structures
Developed a Python/C tool in finding marginal probabilities by compiling and optimizing feed-forward arithmetic circuits
Research abstract accepted to the 2017-2018 issue of RUCS

Safran

Summer 2016

Software Engineering Intern

Designed and documented architecture diagrams for avionic software in C and Assembly, and developed Python scripts to parse aviation requirements and cross-check data flow
Received the NSERC Experience Award, for undertaking an industrial research project in software engineering, as part of UofT's Institute for Multidisciplinary Design and Innovation

University of Toronto Engineering Outreach

Summer 2015

Python Instructor

Designed and delivered a Computer Engineering course in Python to over 120 students at Jr. DEEP, UofT’s engineering summer camp
Led science and engineering workshops for elementary students across the Greater Toronto Area

Education

University of Toronto

Master (M.Sc.) in Computer Science

Interests: Software Engineering, Distributed Systems, Blockchain
Research:
- LMPTs: Eliminating Storage Bottlenecks for Processing Blockchain Transactions [pdf, slides]
  Jemin Andrew Choi, Sidi Mohamed Beillahi, Peilun Li, Andreas Veneris, Fan Long. IEEE ICBC '22 Distinguished Paper Award
- Securing Smart Contract with Runtime Validation [arxiv]
  Ao Li, Jemin Andrew Choi, Fan Long. PLDI 2020
Teaching:
- CSC488: Compilers and Interpreters (Winter 2021)
- CSC207: Software Design (Fall 2020)
- ECE244: Programming Fundamentals (Fall 2020)
- ECE297: Communication and Design (Winter 2020)
- ECE326: Programming Languages (Fall 2019)
Other:
- UofT Engineering Alumni Mentorship: Alumni Mentor
- UofT Saturday Program: Volunteer Tutor
- UKC 2020: Lightning Talk Best Presentation Award
- Devpost: Hackathon Projects

University of Toronto

Bachelor (B.A.Sc.) in Computer Engineering with Honours

Dean's List: Fall 2014 - Spring 2019
Professional Experience Year: Fall 2017 - Spring 2018
Relevant Coursework:
- CSC467: Compilers and Interpreters
- CSC384: Introduction to Artificial Intelligence
- ECE521: Inference Algorithms and Machine Learning
- CSC343: Introduction to Databases
- ECE345: Algorithms and Data Structures
- ECE344: Operating Systems
Clubs:
- Skule Stage Band (Trombonist)
- Korean Engineering Students' Association (IT Director; Webmaster; Event Coordinator)
- Skule Alumni Outreach (Student Outreach Director)
- Track One Mentorship (Head Mentor)
- ECE Ambassador

Projects

Friendle

In a team of 4, I worked on the backend for a matching/hangout suggestion app to help those with social anxiety. We deployed the backend on GCP Cloud Functions (serverless) and integrated it with Firestore. Our project received Telus' Best Mental Health Hack and 2nd place overall at UoftHacks VIII.

Check us out on Devpost!

Recordr.ai: Face-tracking Video Recorder

In a team of 4, I developed a face-tracking video recording app for my capstone project. We used FaceNet and PoseNet, hosted on an EC2 instance, to recognize the speakers' faces and detect gesture-based commands. To communicate with the neural nets, we used AWS IoT to receive real-time commands from the EC2 and relay them to an Arduino motor with a smartphone mount.
You can see a demo of the project here: Google Drive