Hyoungsu Kim
aaa57403@gmail.com
About
My core strength lies in bridging the gap between technical constraints and business needs. I excel at translating ambiguous requirements into efficient, maintainable solutions through proactive communication with cross-functional teams, including non-technical stakeholders. I am highly adaptable and eager to expand my expertise into full-stack development and AI-driven technologies to deliver comprehensive, end-to-end solutions.
Work Experience
Qualitas Semiconductor
Seongnam, South Korea
Software Engineer
Nov. 2024 - now
- Focused on developing reliable backend services and automating infrastructure for semiconductor design workflows.
- Strived to improve system stability and developer productivity by identifying potential bottlenecks and applying appropriate architectural patterns.
- Architecture Evolution: Improved system scalability by transitioning from an initial polling-based design to a Temporal-based Event-Driven Architecture, resolving performance bottlenecks in complex workflow environments.
Pampam
Seoul, South Korea
Backend Developer
Jan. 2024 - Oct. 2024
- Engineered the backend infrastructure for a time-sensitive auction service, focusing on ensuring data consistency and low-latency communication under concurrent traffic loads.
- Real-Time Architecture: Replaced HTTP polling with WebSockets and Redis Pub/Sub to achieve bidirectional data streaming. This design enabled instant price synchronization across horizontally scaled servers, ensuring a fair bidding experience for all connected users.
- Concurrency Management: Designed and implemented mechanisms to handle concurrent access and maintain system integrity during high-traffic auction events.
Education
Kyonggi University
Computer Engineering
Jan. 2018 - Dec. 2024
Skills
Programming Languages
- Python (Expert)
- SQL
- JavaScript (Basic)
Backend & Architecture
- FastAPI
- SQLAlchemy
- Temporal.io
- Event-Driven Architecture (EDA)
- WebSocket
- RESTful API Design
Infrastructure & DevOps
- Docker
- AWS (EC2, ALB)
- CI/CD (GitHub Actions/Gitea)
- Ansible
- Nginx
- Linux
Data & Observability
- PostgreSQL
- Redis
- Zabbix
- Grafana
Security
- Keycloak (SSO/OIDC)
- JWT-based RBAC
- API Security
Projects
Qualitas PMS(Project Management System)
Nov. 2025 - now
- Developed the backend for a task orchestration system designed to manage intricate dependencies in semiconductor design processes.
- Goal: Build a scalable system capable of handling a growing volume of concurrent tasks without performance degradation.
- Approach: Chose Temporal.io (Event-Driven Architecture) early in the design phase to move away from synchronous polling methods that were expected to cause system bottlenecks.
- Implementation:
- Designed workflows using One-off patterns to ensure high availability and minimal resource usage for each task.
- Decoupled event reception from logic execution using a Producer-Consumer model, ensuring the system remains responsive during traffic bursts.
- Used a Reverse Indexing strategy to optimize the mapping between external webhooks and internal task states.
Intelligent Monitoring & Alerting System
Aug. 2025 - Nov. 2025
Engineered an automated operational platform to standardize infrastructure management and ensure reliable incident response within a restricted air-gapped environment.
Problem: Manual server management caused configuration drift, while the existing monitoring system suffered from delivery reliability issues during high-load incidents.
Solution: Built a self-hosted automation suite combining IaC (Ansible) for provisioning and Temporal.io for resilient event processing.
Implementation:
Resilient Alerting: Utilized Temporal Task Queues to isolate alert delivery logic and implemented a throttling mechanism to handle API rate limits (e.g.,Teams), ensuring 100% reliable delivery during traffic bursts.
Dynamic Cooldowns: Integrated Redis to manage dynamic cooldown states, effectively suppressing redundant notification for ongoing incidents and reducing operational fatigue.
Infrastructure as Code (IaC): Developed Ansible Playbooks to standardize OS configurations and automate the rollout of Zabbix agents across 30+ servers, ensuring consistent environments.
Centralized Visibility: Architected a monitoring bridge using Zabbix Proxy to aggregate data from segmented networks into a unified Grafana dashboard.
Qualitas Sheet(Internal Platform)
Nov. 2024 - Jul. 2025
- Developed a centralized platform to manage internal project documentation and approval workflows.
- Problem: Lack of a unified system for authentication and access control made it difficult to manage sensitive project data.
- Solution: Built a secure platform with standardized identity management and a flexible data model.
- Implementation:
- Architected an SSO environment with Keycloak to provide a single entry point for internal services.
- Developed a JWT-based RBAC system within the FastAPI middleware to manage permissions based on department and user rank.
- Designed a PostgreSQL schema to handle the complex, multi-level hierarchical structures required for corporate approval processes.
Real-time Auction Platform with WebSocket
Jan. 2024 - Oct. 2024
- Engineered the backend for a real-time bidding service, focusing on low-latency communication and data consistency.
- Problem: Traditional HTTP communication was too slow for the real-time requirements of an auction closing.
- Solution: Implemented a bidirectional communication model with efficient message queuing.
- Implementation:
- Used WebSockets and Redis Pub/Sub to ensure that bidding events and price updates were synchronized across all users without delay.
- Designed a message ingestion layer using Redis Lists to buffer bids, ensuring FIFO processing and protecting the database from traffic spikes.
- Managed the production environment on AWS, utilizing Auto Scaling and ALB to maintain availability during peak traffic periods.
Certifications
AWS Certified Solutions Architect – Professional
Amazon Web Services (AWS)
Aug. 2025
AWS Certified Solutions Architect – Associate
Amazon Web Services (AWS)
May. 2025