Background

Experience

Six years turning data into production machine learning — plus the languages, frameworks, and tools I reach for most.

Career

Where I've worked

Lead Data Scientist
2022 — Present
Northwind Data & AI
- Own the churn and lifetime-value models that drive a retention program serving 3.4M subscribers.
- Built the team's feature store and MLOps workflow, cutting time-to-production for a new model from weeks to days.
- Mentor four data scientists and set the standards for experiment design, evaluation, and model review.
Senior Data Scientist
2020 — 2022
Meridian Analytics
- Shipped a hierarchical demand-forecasting platform that reduced forecast error by more than half.
- Introduced a company-wide A/B testing framework with variance reduction and automated guardrail checks.
Data Scientist
2018 — 2020
Helix Labs
- Built the first production fraud-detection model, cutting losses while holding false declines flat.
- Automated a manual weekly reporting process with a scheduled pipeline, saving the analytics team a full day each week.

Toolbox

PythonSQLPyTorchscikit-learnSparkTensorFlowPandasXGBoostAirflowdbtMLflowAWS

Also

M.S. in Statistics and B.S. in Computer Science, Seoul National University. Thesis on probabilistic time-series forecasting.

Speaker at PyData Seoul on production forecasting, 2023. Kaggle Competitions Expert and two published workshop papers.

Reach out and I'll gladly share a detailed CV, references, and links to published work.