SOFTWAREENGINEER
Full-stack engineer with production experience in enterprise finance, medical data systems, and workforce tools. Currently building an AI-powered accounting platform at TEN-X (Japan) while maintaining Bee-Time, a workforce app serving 5 retail stores in Sydney.
Experience
Product Users
Growth Driven
End-to-End Delivery
I own the full stack from data modeling and API design through React frontends to cloud deployment on GCP and Firebase. At TEN-X, I built and shipped SAIXAN as the sole developer across every layer.
AI / LLM Integration
Integrated OpenAI and Claude into production workflows. Built prompt templates for consistent code generation, applied prompt caching to cut API costs and latency, and introduced AI-assisted development processes to the team.
Trilingual Communicator
Native Korean, business-level Japanese, and professional English. At Genoray I bridged the Korean dev team and Japanese clients, reducing communication overhead by ~30%.
Cross-Industry Experience
Aviation (4+ yrs), medical X-ray data systems, fintech/accounting, and retail workforce — domain expertise across industries lets me understand business logic fast and build software that fits real operational needs.
- Leading DX (Digital Transformation) projects for enterprise clients, including CRM system development and P&L management platform builds.
- Built SAIXAN, a departmental P&L accounting system with an AI chat assistant from scratch. Now used by 4 internal departments and adopted by 2 external companies.
- Integrated the OpenAI API for bilingual (EN/JP) natural-language financial queries, covering prompt design, context management, and structured output processing.
- Adopted Claude for code generation with reusable prompt templates, applied prompt caching to reduce API costs and response time, and separated system/developer prompts to improve output quality.
- Delivered a real-time P&L dashboard with role-based access, expense approval workflows, budget vs. actuals tracking, and automated Excel exports.
- Own the entire delivery stack as the sole developer: data model, API layer, front-end UI, GCP Cloud Run deployment, and ongoing production support.
- Designed and built Bee-Time, a QR-based attendance and workforce management app. Currently live across 5 retail stores in Sydney with 124 active users.
- Implemented QR check-in with GPS verification via Google Maps API so staff location is confirmed before clock-in is accepted.
- Set up JWT authentication with Google OAuth, an admin dashboard for employee and location management, and automated Excel exports for payroll.
- Maintain the production system day-to-day through bug fixes, performance tuning, and staged feature rollouts.
- Built a DICOM image converter at a medical X-ray manufacturer, enabling the company's viewer software to display X-ray images from 10 third-party device brands (up from 4).
- Developed data transformation pipelines in C++ and C# to parse, validate, and convert proprietary DICOM formats into a unified structure for the in-house viewer.
- Improved ETL processing with batch workflows, stronger validation, and better error handling, contributing to a 25% increase in product sales.
- Served as a bilingual bridge between the Korean dev team and Japanese clients, reducing communication overhead by roughly 30%.
- Ran air route sales initiatives and airport promotional campaigns targeting airline partners, helping bring new routes to Kagoshima Airport.
- Handled tenant billing for airlines and cargo terminals, calculating and invoicing monthly rent, water, electricity, and facility usage fees.
- Designed and launched the official web page for a newly opened Business Jet terminal, covering page layout, content, and coordination with stakeholders.
- Worked as a trilingual liaison (Japanese, Korean, English) across Airline Sales, Passenger Services, and Business Development in a 24/7 environment.
- Coordinated event planning, issue resolution, and daily operational workflows across multiple airport departments.
LiveSAIXAN
Now used by 4 internal departments and adopted by 2 external companies. Finance staff run natural-language queries instead of manual spreadsheet lookups.
A Japanese DX company needed a departmental P&L system where non-technical finance staff could query accounting data in natural language.
Designed and built the entire platform solo. React + TypeScript frontend, Firebase + Express backend, Firestore database, deployed on GCP Cloud Run. Integrated OpenAI API with custom prompt engineering for bilingual (EN/JP) financial queries.
Proprietary system. Architecture overview available on request.
Live · 124 UsersBee-Time
Live across 5 retail stores in Sydney. 124 active users. Store owners reported improved wage accuracy and reduced manual payroll work.
A Sydney cafe group managing 50+ staff across 5 stores needed a reliable attendance system with location-based fraud prevention.
Built QR-based check-in with GPS verification via Google Maps API. Added JWT + Google OAuth auth, an admin dashboard for multi-store management, and automated Excel payroll exports.
ShippedDICOM Image Converter
25% increase in product sales from expanded device support. Reduced KR-JP client coordination overhead by 30% through bilingual technical communication.
The company's X-ray viewer only supported DICOM images from 4 manufacturers, limiting market reach in the hospital sector.
Extended converter compatibility to 10 brands while keeping patient data integrity across hospital PACS systems. Improved ETL pipeline with batch processing, validation, and error handling.
Smart Farm AI
Working prototype with real-time object detection, multi-camera dashboard, alert system, and video analysis upload. Presented as a capstone project at UTS.
A cattle farm needed a way to monitor livestock in real time across multiple CCTV feeds and get automated alerts when animals show abnormal behavior.
Built the AI detection module using YOLOv8 for real-time cattle recognition from live camera feeds. The team built a React dashboard for multi-camera monitoring and a backend API to connect everything.
UTS UniApp
Fully functional dual-interface system handling student enrollment, authentication, and admin operations. Completed with 67 commits across the team.
Needed a student enrollment management system for a university course project, with both command-line and graphical interfaces.
Built two versions of the app: a CLI tool and a GUI using Tkinter. Implemented student registration, login, subject enrollment (max 4), password management, and an admin panel for managing records and grades.
Online Rent Car
Functional car rental platform with end-to-end booking flow, deployed and running on AWS infrastructure.
Needed a web-based car rental system where users can browse vehicles, make reservations, and manage their bookings online.
Built a full booking flow with HTML/CSS/JS frontend and PHP backend. Implemented reservation management, order confirmations, and user booking history. Deployed on AWS Elastic Beanstalk.
“Seoyoon built our entire SAIXAN platform single-handedly — from architecture to deployment. Her ability to own the full stack while integrating AI features was exceptional.”
“Bee-Time transformed how we manage staff across 5 stores. Seoyoon delivered a reliable, polished product and continues to improve it based on our real-world feedback.”
“Seoyoon's bilingual coordination between our Korean engineers and Japanese clients dramatically improved our workflow. Her technical skills in C++ and DICOM were equally strong.”
Let's Work Together
Based in Sydney, open to remote and hybrid. I bring full-stack delivery, AI integration, and trilingual communication to teams building impactful products.