Experience

My professional journey in data and analytics

Work Experience

Dec 2025 - Present Current

Analytics Engineer

Hwahae Global Seoul, South Korea

MAU 1M+

#1 K-Beauty data platform in South Korea. Provides cosmetics ingredient analysis and personalized product recommendations for global consumers.

Key Achievements

  • Internal AI Analytics Agent

    Built and launched a Slack-based NL2SQL AI agent (Cloud Run + Claude API + BigQuery MCP + DataHub MCP), adopted by 70% of the company for self-serve analytics.

  • Advertising Data Mart

    Designed end-to-end B2B ad performance SSOT — the company's first unified view of ad contracts, revenue, and performance across all ad products.

  • CDC Pipeline Architecture

    Architected 3-layer CDC pipeline (RDS → BigQuery) using GCP Datastream for near real-time data ingestion with cost-optimized queries.

  • Production Data Pipelines

    Built pipelines serving live product features (trending keywords, marketing notifications) and CRM targeting via Braze CDI integration.

BigQuery Airflow Datastream Claude API Python
Jul 2025 - Dec 2025

Analytics Engineer

Wrtn Technologies Seoul, South Korea

MAU 6M+

Largest AI portal in South Korea offering free unlimited generative AI. Sole Analytics Engineer managing data across three major products.

Key Achievements

  • DW Layer Enhancement

    Designed a new Core Layer and standardized the DW hierarchy, ensuring consistent metric definitions and faster data access.

  • Automated Specification Generation

    Built an automated documentation pipeline using dbt macros to generate and maintain data specifications, improving Text2SQL AI Agent accuracy.

  • Idempotent dbt Incremental Macros

    Developed and standardized dbt incremental strategy macros, replacing legacy batch scripts with a robust and idempotent approach.

BigQuery dbt Airflow DataHub Python
Mar 2025 - Jun 2025

Data Engineer

Coinone Seoul, South Korea

MAU 600K+

One of South Korea's top cryptocurrency exchanges, part of the "Big Four" alongside Upbit, Bithumb, and Korbit. One of three Data Engineers building ELT pipelines and dbt-based data marts.

Key Achievements

  • Marketing Event Settlement Automation

    Standardized settlement logic using BigQuery TVFs and built reusable templates integrated with internal Admin system.

  • PII Masking Pipeline

    Implemented Terraform-coded infrastructure invoking GCP Sensitive Data Protection APIs as BigQuery Remote Functions.

BigQuery dbt Airflow Kafka Connect Airbyte Terraform ArgoCD EKS
Jan 2024 - Feb 2025

Analytics Engineer

IoTrust (D'CENT Wallet) Seoul, South Korea

MAU 70K+

Maker of D'CENT, the world's first biometric hardware crypto wallet. First and only data professional at the company, leading all data-related decisions and initiatives.

Key Achievements

  • DW & Data Mart Architecture

    Designed a dbt-based DW and data mart structure for internal analytics and SaaS BI, improving query efficiency and semantic consistency.

  • BI Dashboard Operations

    Reorganized Redash around KPI dashboards and introduced Metabase for no-code BI access and broader data democratization.

  • Event Taxonomy Management

    Defined event and parameter schemas, built QA processes, and standardized documentation for consistent data collection.

  • Airflow Pipeline Automation

    Established initial Airflow workflows and Slack notification bots to automate data alerts and monitoring.

BigQuery dbt Airflow Redash Metabase Python Slack API
Jun 2022 - Sep 2023

Data Analyst

IoTrust (D'CENT Wallet) Seoul, South Korea

MAU 70K+

Maker of D'CENT, the world's first biometric hardware crypto wallet. First and only data professional at the company, leading all data-related decisions and initiatives.

Key Achievements

  • Analytics Environment Setup

    Designed and implemented an end-to-end stack (GTM → GA4 → BigQuery → Redash) to enable analytics capabilities.

  • A/B Testing Task Force Lead

    Founded an A/B Testing TF, established frameworks, and oversaw execution and analysis for data-driven experimentation.

  • Conversion Rate Optimization

    Improved purchase conversion rate (payment start → complete) by 32%p through funnel analysis and optimization.

BigQuery GA4 GTM Redash Amplitude Python
Mar 2020 - Apr 2021

VBA Programmer (Contract)

Product Asset Consulting Seoul, South Korea

Completed 7 independent VBA engineering automation projects for Hyundai Motor's engineering workflows with 100% personal contribution.

Excel VBA Automation
Apr 2019 - Oct 2019 US Experience

Finance Intern

PeopleFund Austin, Texas, USA

US Treasury-certified CDFI and SBA Lender with $1.2B+ economic impact in Texas, supporting 25,000+ jobs. Analyzed loan portfolio data and presented weekly insight briefings in staff meetings.

Excel Data Analysis Financial Modeling
Mar 2018 - Jun 2018

Data Entry Intern

Korea Listed Companies Association Seoul, South Korea

Collected, cleaned, and entered financial statements of listed companies. Gained early experience in automating repetitive workflows using Excel and VBA.

Nov 2017 - Jan 2018

Equity Research Assistant Intern

Heungkuk Securities Seoul, South Korea

Extracted and visualized financial data for analyst reports using Bloomberg Terminal and Excel.

Education

Sep 2020 - Feb 2023

M.Eng. in AI Big Data

Kookmin University, Seoul

Key Courses: Python Programming, Data Modeling & SQL, Statistics, Machine Learning, Deep Learning, NLP, Vision AI

GPA 4.50/4.50 (1st Semester) - Academic Excellence Scholarship

Mar 2010 - Aug 2018

B.A. in Philosophy & B.B.A. in Finance

Chung-Ang University, Seoul

Key Courses: Logic, Business Administration, Marketing, Economics, Financial Economics, Mathematical Statistics

Dean's List Scholar (Top Student, 3rd & 4th Semester)

Senior Representative, Student Council (7th Semester)

Certifications & Courses

Data Engineering

  • Data Engineering Zoomcamp DataTalksClub
  • dbt Bootcamp Udemy
  • Data Warehouse Udemy
  • Kafka Udemy

Infrastructure & DevOps

  • Deploying Airflow on EKS with Helm, GitOps, and CI/CD Udemy
  • Kubernetes Inflearn
  • Airflow Inflearn
  • Git/GitHub Inflearn

Programming & Analysis

  • The Advanced SQL Course Udemy
  • Data Analyst with Python Track DataCamp
  • Excel/VBA for Creative Problem Solving Coursera

Interested in working together?

I'm always open to discussing new opportunities in data engineering and analytics.