• Designed and built backend API server by myself from scratch; currently serving for 400k MAU - using NodeJS, ExpressJS, MySQL on AWS.

• Developed "Todo Math" iOS and Android app, award-winning math learning app for kids; reached 5M downloads on AppStore over 4 years; built on the cocos-2d framework using Objective-C/Java/C++.

• Designed and built analytics API server for event logging.

• Developed web dashboard for teachers and internal dashboards using NodeJS, HTML5, CSS3, AngularJS, and jQuery on AWS.

• Developed "Kitkit School" Android Tablet app; a finalist for Global Learning XPRIZE competition.

• Built and Managed AWS Cloud Environments - ElasticBeanStalk, Lambda, CloudWatch, RDS, S3, ELB, IAM.

• Built responsive company and product websites using HTML/CSS/jQuery, SASS

• Worked with a small team using scrum/agile methodology with JIRA/Slack/Basecamp.

• Performed a government project for Supreme Court of Korea - Adult Guardianship System

• Analyzed system requirements, led a team over 20 and resolved technical issues as a technical director

• Designed and built web applications using Java, Spring Frameworks, Oracle

• Performed a government project for Supreme Court of Korea - Family Relationship Registration System

• Designed data schema and built relational database; planned and migrated over hundred millions data; optimized and partitioned SQL Queries

• Implemented registering and printing modules using Java, Spring Frameworks, Oracle DB, Reporting Solution