$ Data scientist · Machine learning · Seoul

I turn data into decisions

I build machine learning systems that ship — from feature pipelines to production models — and I measure their impact in dollars, latency, and error rate. Explore the case studies below.

Data scientist workspace with charts on screen at night

How I work

From messy data to models people trust

I care less about the fanciest architecture and more about whether the model holds up in production and moves a real metric. Here's how I approach the work.

End-to-end ownership

I own the full path — data extraction and feature engineering, training and evaluation, then serving, monitoring, and retraining. No hand-off gaps where models quietly break.

Rigorous evaluation

Offline metrics are table stakes. I back every model with holdouts, causal experiments, and calibration checks so a lift is real and not just a lucky slice of the data.

Impact you can measure

Every project below states the outcome in the units the business cares about — churn points, forecast error, response time, revenue — not just the algorithm I reached for.

Have a hard data problem?

Whether it's a model that stalled in production or a question your dashboards can't answer, I'd love to hear about it. Let's talk.