I’m a full-stack developer with a strong focus on Next.js, Node.js, and Java, working mainly on backend-heavy and system-level applications. Most of my experience is in building APIs, business logic, and data-driven systems that need to be stable and easy to operate in production. I’ve worked on platforms in healthcare, logistics, manufacturing, and e-commerce, including systems for COVID testing, Chronic Care Management (CCM), Remote Patient Monitoring (RPM), ERP, WMS, and TMS. A lot of my day-to-day work involves designing REST or GraphQL APIs, integrating third-party services, and connecting modern web applications to existing enterprise systems. On the frontend, I use Next.js to build practical, production-ready applications, usually paired with Node.js on the backend. On the enterprise side, I’ve spent many years working with Java (Spring-based systems), especially for large, long-running services where reliability and performance matter. I’m comfortable working with AWS, Docker, and CI/CD pipelines, and I usually take responsibility for deployment, environment setup, and ongoing maintenance. I also have strong database experience with Oracle, MySQL, and MS SQL, including schema design and performance tuning. I prefer clean, straightforward solutions and systems that are easy for other developers to understand and maintain. I’m used to owning features end-to-end and working closely with product, operations, and other engineers to ship and support real production systems.

Hwan Joo Jang

I’m a full-stack developer with a strong focus on Next.js, Node.js, and Java, working mainly on backend-heavy and system-level applications. Most of my experience is in building APIs, business logic, and data-driven systems that need to be stable and easy to operate in production. I’ve worked on platforms in healthcare, logistics, manufacturing, and e-commerce, including systems for COVID testing, Chronic Care Management (CCM), Remote Patient Monitoring (RPM), ERP, WMS, and TMS. A lot of my day-to-day work involves designing REST or GraphQL APIs, integrating third-party services, and connecting modern web applications to existing enterprise systems. On the frontend, I use Next.js to build practical, production-ready applications, usually paired with Node.js on the backend. On the enterprise side, I’ve spent many years working with Java (Spring-based systems), especially for large, long-running services where reliability and performance matter. I’m comfortable working with AWS, Docker, and CI/CD pipelines, and I usually take responsibility for deployment, environment setup, and ongoing maintenance. I also have strong database experience with Oracle, MySQL, and MS SQL, including schema design and performance tuning. I prefer clean, straightforward solutions and systems that are easy for other developers to understand and maintain. I’m used to owning features end-to-end and working closely with product, operations, and other engineers to ship and support real production systems.

Available to hire

I’m a full-stack developer with a strong focus on Next.js, Node.js, and Java, working mainly on backend-heavy and system-level applications. Most of my experience is in building APIs, business logic, and data-driven systems that need to be stable and easy to operate in production.

I’ve worked on platforms in healthcare, logistics, manufacturing, and e-commerce, including systems for COVID testing, Chronic Care Management (CCM), Remote Patient Monitoring (RPM), ERP, WMS, and TMS. A lot of my day-to-day work involves designing REST or GraphQL APIs, integrating third-party services, and connecting modern web applications to existing enterprise systems.

On the frontend, I use Next.js to build practical, production-ready applications, usually paired with Node.js on the backend. On the enterprise side, I’ve spent many years working with Java (Spring-based systems), especially for large, long-running services where reliability and performance matter.

I’m comfortable working with AWS, Docker, and CI/CD pipelines, and I usually take responsibility for deployment, environment setup, and ongoing maintenance. I also have strong database experience with Oracle, MySQL, and MS SQL, including schema design and performance tuning.

I prefer clean, straightforward solutions and systems that are easy for other developers to understand and maintain. I’m used to owning features end-to-end and working closely with product, operations, and other engineers to ship and support real production systems.

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Experience Level

Expert
Expert
Expert
Expert
Expert
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Expert
Expert
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Expert
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Intermediate
Intermediate
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Language

Korean
Fluent
English
Intermediate

Work Experience

Project Manager & Full-Stack Developer at eKlotho, Inc
May 1, 2020 - Present
Led the design and development of healthcare applications including Chronic Care Management and Remote Patient Monitoring portals. Built COVID-19 test lab management platforms and integrated hardware devices for live data tracking.
Full Stack Developer at Isware ORM
May 1, 2018 - January 1, 2019
Led infrastructure design and project lifecycle for an upgraded logistics management system. Developed and maintained systems using Java, Spring Framework, and Laravel.
Oracle Database Administrator & Transport Developer at POS Malaysia
March 1, 2016 - April 1, 2018
Supported development teams with Oracle database setup and maintenance. Managed database infrastructure and handled integrations for operations, tracking, inventory, and customer care.
Magento Front & Backend Developer at CJ Celeshop
May 1, 2014 - February 1, 2016
Analyzed and enhanced client-server management systems, upgraded CJ Fashion Mall from Magento 1.9 to 2.4, and integrated legacy modules.
Magento Front & Backend Developer at Lotte in Vietnam
June 1, 2013 - February 1, 2014
Supported development of logistics systems and upgraded Magento 2.1 Back Office and Seller Portal for improved performance and reliability.
Back End Developer at Samsung ESL / UBTO USA
October 1, 2012 - May 31, 2013
Built back-end logic and integration for Electronic Shelf Label projects; developed REST APIs and data integration for cross-regional deployments.
Full Stack Developer at Radio Korea
January 1, 2010 - April 30, 2012
Rebuilt the Radio Korea website and developed mobile applications for iOS and Android; implemented a community board and real-time updates.
Back End Developer at Korean Air
August 1, 2008 - June 30, 2009
Designed air cargo data structures and live tracking interfaces; implemented server-side logic in Java EE to support cargo operations.
Cobol Data Transfer & Backend Developer at National Health Insurance Corporation Korea
July 1, 2007 - July 31, 2008
Designed COBOL data schemas and migrated legacy data to Oracle-based structures; supported backend development and data processing tasks.
Breakdown Developer at KIA Motors R&D Center
January 1, 2006 - June 30, 2007
Designed and implemented car breakdown tracking data models; contributed to data analysis, testing, and system integration for vehicle Diagnostics.

Education

Associate Degree at Soongsil College
January 1, 2000 - January 1, 2002
System Administration at AC OS System 3300 (Samsung Electronics)
January 11, 1998 - January 19, 1998
Oracle Tools at Oracle Korea Education Center
January 11, 2000 - January 23, 2000

Qualifications

Industrial Engineer Information Processing
July 31, 2005 - January 18, 2026

Industry Experience

Healthcare, Computers & Electronics, Software & Internet, Manufacturing, Education, Transportation & Logistics, Professional Services, Retail