Kyoung-Ryul Park
Software Engineer
Incheon,46
Summary
Backend engineer with hands-on experience operating high-traffic production systems and optimizing infrastructure efficiency.
Strong in distributed systems thinking, cost-aware architecture design, and ownership-driven problem solving.
Motivated to join AWS to deepen my understanding of large-scale cloud infrastructure and reliability engineering practices.
My long-term goal is to become a globally competitive systems engineer who builds scalable and resilient cloud-native architectures.
Overview
3
3
years of professional experience
1
1
Certification
Work History
Co-Founder & CTO
LoadIT.Cor (NestJs, Spring, AWS Etc...)
08.2025 - Current
- Lead backend development and overall project coordination for a used-car export platform serving international markets.
- Architected and implemented separate user-facing and admin systems using NestJS and Spring, improving maintainability and access control.
- Implemented an automated payment cancellation workflow using a message queue-based asynchronous processing architecture, ensuring reliable transaction rollback.
- Integrated Toss Payments PG to build a secure and scalable payment processing system.
- Enhanced application security by configuring Web ACL rules to mitigate command injection risks and automated static code scanning via GitHub Actions CI pipelines.
- Implemented geospatial distance-based filtering using PostGIS (ST_DWithin) to calculate precise meter-level proximity queries.
- Implemented a custom OAuth authentication system leveraging identity provider, enabling unified cross-platform login.
- Applied the Proxy Pattern to abstract and manage external platform API integrations, improving modularity and reducing coupling.
Backend Developer
Revibio (NestJs, AWS Etc...)
02.2023 - 07.2025
- Built and operated a scalable AWS-based production system handling 1,200 RPS, leveraging EC2, RDS, and load balancing.
- Resolved race conditions in a distributed environment using Redis-based distributed locking (ElastiCache).
- Reduced image payload size by up to 90% through a custom image processing pipeline, improving network efficiency and lowering bandwidth costs.
- Reduced EC2 costs by 50% through performance profiling, CPU/memory optimization, and right-sizing instances.
- Achieved 75% reduction in RDS costs by optimizing query execution plans, indexing strategies, and database schema design.
- Refactored transactional boundaries by removing external API calls inside DB transactions and implementing compensating transactions to ensure eventual consistency across services.
- Designed and implemented a high-throughput push notification system using an asynchronous message queue architecture (SQS).
- Improved log query performance by introducing horizontal partitioning, reducing query latency under high write workloads.
- Applied CQRS and read replication to offload read-heavy traffic and improve system scalability.
Education
B.S. - Computer Science
Inha University
Incheon, South Korea 04.2001 -
Skills
Team collaboration
Software architecture
Problem-solving abilities
Message broker experience
API design and development
Asking to Team
Certification
AWS Solution Architecture - Associate (deb6304db22e4343b77cb549bb5e3f38)
Timeline
Co-Founder & CTO
LoadIT.Cor (NestJs, Spring, AWS Etc...)
08.2025 - Current
AWS Solution Architecture - Associate (deb6304db22e4343b77cb549bb5e3f38)
07-2025
Backend Developer
Revibio (NestJs, AWS Etc...)
02.2023 - 07.2025
B.S. - Computer Science
Inha University
04.2001 -
Military Service
Completed (Alternative Service – Industrial Technical Personnel Program)