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.
$ Data scientist · Machine learning · Seoul
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.

How I work
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.
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.
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.
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.
Selected work
Production machine learning across churn, forecasting, NLP, experimentation, fraud, and recommendations. Click any card for the role, methods, and measured impact.
FeaturedA gradient-boosted churn model that scores every subscriber nightly and feeds a retention playbook.
FeaturedA hierarchical forecasting system that predicts SKU-level demand across 900 stores two weeks out.

A transformer-based classifier that routes and prioritises inbound support tickets in real time.

A statistical engine that powers trustworthy A/B tests and untangles cause from correlation.

A streaming anomaly-detection model that scores transactions for fraud within 50 milliseconds.

A two-tower recommender that powers homepage and email personalisation for millions of users.
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.