I’m a software engineer with 6+ years of experience in areas including ML engineering, data engineering, and backend software engineering. I am interested in delivering real-world business value through a data-driven software system.

☎️ Contact information

📧 hyeonseop@ls-al.me

🔗 https://www.linkedin.com/in/hyeonseop/

👨🏻‍💻 Work experience

Technical Lead

Grinder, Daejeon, Korea – (Sep 2020 - Present)

Designed and developed B2C commerce platform capable of 3rd party sales.

Set up data pipelines to collect and analyze user behavior logs.

Led machine learning projects to strengthen content-based commerce.

Machine Learning Engineer

PUBG, Seoul, Korea – (Jul 2018 - Aug 2020)

Designed and developed real-time A/B testing platform for global services with 1M+ CCU.

Improved service sales by establishing real-time recommendation system using Bayesian Inference and MAB.

Data Engineer

Hyperconnect, Seoul, Korea – (Sep 2016 - Jun 2018)

Developed data pipelines that handles user behavior logs for large-scale global services.

Built a real-time push transfer pipeline and conducted experiments on push message personalization.

Software Engineering Intern

Google, Mountain View, CA, USA – (Jan 2016 - Jul 2016)

Implemented network congestion control mechanisms for data center SDN.

🛠 Skills

💻 Tech Stacks

Big data and data pipelines frameworks

Spark, Flink, BigQuery, Athena, ElasticSearch, HBase, Airflow

Containers and cloud-based infrastructures

Docker, Kubernetes, Prometheus, Helm, AWS, GCP, Terraform

Backend software engineering

Python, Golang, Java, Kotlin, Django, Spring, gRPC, OpenAPI

Collaboration

Jira, Confluence, Notion, Git flow, GitHub PR review process

🗣 Languages

Korean

Native speaker

English

Upper-intermediate speaker

🏆 Honors and Talks

Talk “머신러닝도 A/B 테스트부터” (A/B Testing for Machine Learning)

Krafton Developer Conference 2019

Talk “그치만 이렇게 하지 않으면 A/B 테스트 시켜주지 않는걸” (Things had to be done for A/B Test)

Nexon Developer Conference 2019

Talk “When seasonality meets Bayesian: Decomposing seasonalities in Stan”

StanCon 2019

ACM-ICPC World Finalist

ACM-ICPC World Finals 2015, 15th place (KAIST)

DEF CON CTF Final Participant

DEF CON 24 CTF (2016), 5th place (KaisHack GoN)

DEF CON 22 CTF (2014), 10th place (KAIST GoN)

📚 Education

Bachelor's Degree in Computer Science

KAIST School of Computing, Mar 2013 - Aug 2021