Hi there 👋, I'm Stuart. I aim to be both an entrepreneur and a dedicated computer engineer. I'm passionate about developing new products, optimizing complex systems, learning new technologies, and building a great team. I love the feeling of tackling novel challenges from scratch and pushing the boundaries of what's possible in computer science. I co-founded Blux (formerly Z.Ai), an AI startup specializing in empowering e-commerce and online content platforms through AI-driven personalization. Blux raised $1.7M+ USD from SpringCamp and Primer Sazze, and personalized over 10 million Korean users' online journeys monthly. Leading Blux was an exciting journey building robust and scalable ML systems and dedicating myself to effectively leading and growing our engineering team. I briefly worked as the DevOps & MLOps Lead at Linq (Techstars '23), focusing on developing efficient software architectures for operating Retrieval-Augmented Generation (RAG) products designed for professional services firms. I am now pursuing my Master of Science degree in Computer Science (MSCS) at Stanford University. In addition, I'm a guitarist, sound engineer, and composer with two publicly released albums. I've been a lead guitarist and producer in various rock bands since 2008. I'm always up for a conversation about rock music and audio. Feel free to connect with me via my email or LinkedIn 😁
Education
Stanford University
M.S. in Computer Science
- Recipient of the merit-based Kwanjeong scholarship ($60,000).
Seoul National University
B.S. in Computer Science and Engineering
- GPA: 4.21/4.3 (class rank: 1st).
- Member of the College of Engineering Honor Society.
Experience
Linq (Techstars '23)
Software Engineer (DevOps & MLOps Lead)
- Engineered and maintained a resilient multi-cloud RAG infrastructure across AWS and Azure.
- Migrated all application workloads to a K8s environment and implemented IaC for existing cloud resources using Terraform.
- Enabled detailed monitoring of customers' LLM usage through the EFK stack, Prometheus, and Grafana.
- Established core DevOps practices, including GitOps, autoscaling, CI/CD, monitoring, logging, and alarming, with Argo CD, Karpenter, GitHub Actions, Elasticsearch, Fluentbit, Kibana, Prometheus, and Grafana.
Blux (formerly Z.Ai)
Co-Founder and CTO
- Co-founded and grew Blux to serve 10M+ monthly users with $1M+ in annual revenue; Blux is an AI SaaS startup specializing in real-time recommender systems for e-commerce.
- Secured $1.7M in funding and received a $10M valuation in South Korea.
- Designed a Kubernetes-based e-commerce recommender engine that handles 1B+ requests monthly and trains/deploys 100+ ML models daily (featured in the official AWS Blog).
- Engineered a robust, scalable, multi-tenant MLOps architecture that automates data gathering, model training, deployment, and monitoring, and maintained 99.95%+ service uptime since the initial product launch.
- Achieved 90% automation of SaaS product delivery by developing microservices for customer data collection and recommender model serving using FastAPI and gRPC.
- Developed and documented the Blux SDK (Python, Java, Kotlin, JavaScript, TypeScript, PHP, and Swift).
- Built Transformer-based recommender models with TensorFlow, leading initial customers to switch from a comparable AWS product to Blux for superior click-through rates.
- Initiated and managed multiple engineering projects, including no-downtime ECS -> K8s migration, Cafe24 (Korean Shopify) product launch, and tenant onboarding automation (using Jenkins, Argo CD, and Airflow).
- Recruited, built, and led an agile team of 15+ engineers.
Architecture and Code Optimization Lab, Seoul National University
Research Assistant (Advisor: Prof. Jae W. Lee)
- Designed and implemented a novel embedding clustering algorithm in C++, reducing the main memory access by up to 44% in commercial deep learning recommendation models (DLRMs).
- Co-authored an academic paper accepted at ASPLOS 2021, a top-tier CS systems conference.
- Analyzed query patterns in recommendation dataset with hyperpartitioning algorithms.
- Performed support tasks including data preprocessing, analysis, and algorithmic prototyping in C++ and Python.
Music and Audio Research Group, Seoul National University
Research Assistant (Advisor: Prof. Kyogu Lee)
- Implemented an audio processing architecture using CNN, cGAN, super-resolution, and the Griffin-Lim algorithm, contributing to a commercial singing voice synthesis project.
- Performed data labeling on audio and MIDI data with millisecond-precision using Logic Pro and Python, preparing 30+ songs for model training.
- Led 6 lab seminars on advanced Python, teaching a group of graduate students with no prior technical background.
Projects
SampyoNet
University Team Project
- Developed a TensorFlow-based deep learning model and React.js-based mobile application for automated gravel quality assessment in concrete manufacturing.
- The project was requested by Sampyo, a leading cement manufacturer in South Korea.
LLVM Compiler Optimization
University Team Project
- Optimized LLVM compiler using C++ to enhance assembly code performance.
- Secured 2nd place among 13 teams in an LLVM optimization competition at Seoul National University.
Homemade Neural Network
Personal Project
- A deep learning framework written using only native Python (not even NumPy).
Five-in-a-row with AI
Personal Project
- A game of five-in-a-row, with GUI and an AI opponent.
- GUI and AI written in native Python.
- AI implemented using minimax algorithm.
Skills
Languages
English, Korean
Programming Languages
Python, Java, C, C++, JavaScript, TypeScript, HTML, CSS, SQL, Shell
Libraries & Frameworks
FastAPI, Flask, React.js, Redis, PostgreSQL, NumPy, Pandas, Spark, TensorFlow, PyTorch
DevOps & MLOps
Linux Administration, Docker, Kubernetes, Helm, AWS (VPC, EC2, ECS, EKS, EBS, ELB, S3, RDS, DynamoDB, ElastiCache, Lambda, API Gateway, SMS, SNS, SQS, Glue, MWAA, Route53, CloudFront, CodePipeline, CodeBuild, CloudFormation, Secrets Manager, KMS, CloudWatch, CloudTrail), Azure, Terraform, GitHub Actions, Jenkins, Argo CD, Elasticsearch, Logstash, Fluentbit, Kibana, Prometheus, Loki, Grafana, Apache Airflow, MLflow, TensorFlow Serving, Karpenter, Sealed Secrets, Milvus
More About Me
Music
I am a guitarist, sound engineer, and composer with 2 albums released on major streaming platforms such as Spotify and Apple Music. Since 2008, I have served as the lead guitarist for various rock bands, performing in 2~3 rock concerts every year before COVID-19.
U.S. Army
I served as a Combat Medic in a U.S. Army cavalry unit from November 2017 to August 2019 (21 months). This was possible through the Korean Augmentation to the United States Army (KATUSA) program, which allowed me to fulfill South Korea's military service requirement while serving in the U.S. Army.