- Experienced software engineer with a passion for distributed systems,
scalability problems, and dealing with a large amount of data.
- Actively seeks for opportunities to boost the productivity of the team by
building internal tools.
- Keeps communication skills honed by actively engaging in conversations,
public speeches, and ritually writing daily journals and various social media
posts of substantial lengths.
Senior Software Engineer @Coupang
Korean version of Amazon.com; largest e-commerce, logistics company
- Led other senior engineers who are partially involved in this project.
- Wrote Spark jobs for extract, transform, load (ETL) tasks, Airflow jobs for
- Contributed to Secor project
(from Pinterest) to fulfill the needs of this project.
Inter-domain Logistics State Management System
- Consolidated duplicated features across multiple internal teams into a common
microservice to eliminate data inconsistencies and to promote efficiency.
- Wrote code to handle write-heavy workloads with Cassandra.
- Wrote Spark jobs in Scala for data validation, fully automated with
Internal Tools & Extracurricular Activities
- Built a command line tool in Golang to issue temporary AWS access keys with
AD FS and AWS STS to reduce wasted time for myself and my colleagues.
- Led an unofficially-organized Python class.
Software Engineer @Nexon
Largest gaming company in South Korea, servicing +100 titles in +190 nations world-wide
- In-game natural environment that resembles that of the real world
- Number crunching with OpenCL and C# math library
- ECS, ECR, data pipeline
- Cost saving (est. $300,000/year) with architectural revisions
- Implementing precautionary measures: data validator, auto-scaling
- Public speech on this topic: Automating Mother Nature @AWS re:Invent 2017
- In-game marketplace where players exchange goods with money and vice versa
- Inter-database transactions (Couchbase ↔︎ AWS Aurora)
- Complex search query support with Elasticsearch
- Driving most of technical decisions
- Wheelhouse: Automated Python package pre-build system for internal PyPI repository
- Game world packaging and distribution tools for internal customers (game designers, non-tech users)
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Software Engineer @Spoqa
Mar 2014 - Jul 2014
Seoul, South Korea
- Built a customer-facing Android app
- Built a backend for commercial loyalty service
Research Programmer @University of Arizona
Jun 2010 - Jun 2011, Tucson, AZ
- Developed internal tools to conduct machine learning research
MS in Computer Science @University of Arizona
Aug 2011 - Dec 2013
Tucson, AZ, USA
BS in Computer Science, Mathematics @University of Arizona
Jan 2006 - Dec 2010
Tucson, AZ, USA
- Occasionally, but persistently taking classes from Coursera, Udacity
- Machine Learning
- Design of Computer Programs
- Computational Finance
- Founding and leading an unofficial research paper reading group in Nexon (2015)
Discussed the architecture that we settled on for algorithmic generation of
game content in a large scale with a number of components provided by Amazon
Web Services such as distributed messaging queues (SQS), containerized
application clusters (ECS), and object storages (S3).
Discussed how we built an automated pipeline to supply natural resources. Due
to the sheer size of the in-game world, the environment simulation is performed
on-demand, within a limited geographic boundary, in accordance with player
Discussed how we built an in-game environment simulator with OpenCL to handle a
massive parallel processing. The primary purpose of the simulator is to provide
natural resources based on realistic simulations by taking a number of
geographic features, such as topography, temperature, humidity, soil fertility,
Patents & Research Papers
Nexon decided to file a patent with the work referred above as natural
environment simulation. I was listed as a co-author along with the game
designer who pioneered the concept.
Discusses how human-instructable computing can be achieved. That is, how an
electronic student can be taught using the same natural instruction methods
Open Source Activities
Contributions to others
- pandas-datareader: Extract data from a wide range of Internet sources into a pandas
- secor: Kafka log persistence.
- gspread: A Python library to access and manipulate Google Spreadsheets.
My own projects
An improvised marketplace to sell underused personal belongings where every
auction starts at KRW 1,000 (approximately USD 1).
Set of code for personal asset management and quantitative investment.
Providing 127GFLOPs on average to tackle difficult scientific problems such as
climate modeling, discovering large prime numbers, and generating accurate
three-dimensional dynamic models of stellar streams in the immediate vicinity
of the Milky Way galaxy.
This project had started in March of 2011 in an attempt to help the general
public to be alerted regarding the spread of radiation and other radioactive
materials originated from the catastrophic incident in the Fukushima nuclear
power plant in Japan, by visualizing city-wise radition levels in near real