• Designing and implementing new features and functional enhancements on the Cepheid OS team for the Touchscreen & R3 system. Stacks: Java 11/17/21, Spring Boot, Angular, C++, MS-SQL, REST API, TLS, PKI, Codesign, LDAP, Vibe Coding etc.

• Solved various mission-critical challenging problems, improved and expanded the system's stability and usability.

Working as a full-stack senior software engineer.

• Upgrading GeneXpert Xpress molecular analysis software to next-generation software on the Nexsys project team. Stacks: Java 8, Spring, Angular, C++, MS-SQL, REST API, XML etc.

• Contribute to implementing new features, improving service performance, user interface, and code review.

• Co-working with software engineer and quality assurance testing engineer.

• Worked as a contractor at Payment Team of MAP-PD. RS Software is the contract company.

• Performed successfully improve functionality, performance, code quality, and a bug fix for 20+ payment gateway and common services. Stacks: Java 8, Vert.X, Spring, Redis, Hazelcast, ZeroMQ, Kafka, Oracle, REST API, XML, Vault, Consul etc.

• Contributed to decompose 10+ payment gateway codes and containerize it to support micro-service and successfully deployed to production – Docker swarm - and Kubernetes environment.

• Mentored Junior/Senior Software Engineer and collaborated with other teams on Austin and India.

• Contributed to implement 8+ large and small solutions for personal, enterprise and government agencies.

• Led full project to design and implement a mobile service that provides price information of crypto-currencies. Stacks: Java 8, Spring Boot, Angular, Ionic, Jenkins, Docker, and AWS-S3/EC2/CloudFront/RDS/MQ.

• Redesigned and launched a log management and monitoring product for the directory server. Stacks: Java 8, Spring Boot, MongoDB, Redis, RabbitMQ, MariaDB, AngularJS, and LDAP.

• Participated in implement an LDAP-to-various storage data synchronization system. Stacks: Spring framework, AngularJS, NodeJS (REST Proxy), MongoDB.

• Designed user access control solutions and identity management solutions; implemented proxy server for user access control, protocol layer module, data en/decrypt module, data synchronization module, and web service.

• Participated in design and implement PKI-based key escrow system (Key Management Infrastructure - KMI) project. Received an award from the Korean Prime Minister. Stacks: Unix C/C++, Visual C++

• Designed and implemented TCP/IP packet monitor/controller system and web-based client service for management. Stacks: Unix C/C++, Spring, Servlet, Applet, REST, JSON.

• Performed improvement of performance, stability, and reliability and strengthen security issues by refactoring logic of various products.