CTO
2021 - 2022Pulsen- Led a Cloud-based SaaS app development as a tech lead.
- Developed the SaaS app as a tech lead with hands-on skills.
- Worked with multi-cloud platforms such as GCP, Google Firebase, and AWS for the SaaS app development.
- Utilized Agile methodologies such as Scrum, sprint, and retrospective.
- Made use of software engineering methodologies such as code reviews and design specs.
Technologies: Python 3, JavaScript, Node.js, Vue, Amazon Web Services (AWS), Google Cloud Platform (GCP), FirebaseTech Lead
2018 - 2020Calm Island- Led tech initiatives on the adaptive learning platform.
- Led multiple projects, such as the mobile apps and data pipeline project simultaneously, targeting many countries such as China, Sri Lanka, and Vietnam.
- Managed 15 back- and front-end engineers as a tech lead.
- Designed and led a big data platform targeting customers in many countries.
Technologies: Amazon Web Services (AWS), Jenkins, Git, Microsoft SQL Server, JavaScript, React, Python, Go, JavaTech Lead
2018 - 2018Kidaptive- Led tech initiatives on the big data/machine learning platform, ingesting eight million events daily.
- Supported multiple large companies using the big data platform in Korea.
- Communicated between software engineers working at HQ and Korean customers.
- Designed and coded APIs for customers in Korea and reduced development costs to 50%.
Technologies: Amazon Web Services (AWS), Apache Hive, Spark, HBase, Hadoop, Spring, PostgreSQL, Jenkins, Git, Oozie, HDFS, Apache ZooKeeper, Apache Kafka, Python, JavaSenior Software Engineer
2014 - 2017Ziontech Korea- Provided a solution to the challenge of the same UI as the existing heavy traffic iPhone app by designing and developing an Android application as a lead.
- Enabled messaging between components throughout the entire architecture by developing a message-producing broker library with Kafka.
- Provided a solution to SSO development needs by customizing an open-source software CAS.
- Reduced costs for back-end API development by 50% by refactoring an open-source project, eSCIMo, and debugged existing bugs earlier than scheduled.
- Managed, assigned, and communicated programming tasks to teams of engineers in the US, Korea, and India branches in a multi-lingual environment.
Technologies: HTML5, CSS3, Backbone.js, JAX-RS, JPA, SQL, HSQLDB, eSKIMo, Docker, Apache ZooKeeper, Jenkins, GitHub, CAS, Apache Kafka, JavaScript, Android, JavaPHP Developer
2015 - 2015Adam Fordham Consulting (via Toptal)- Created website administrator modules using PHP, MySQL, and JavaScript.
- Created front-end modules using JavaScript, jQuery, and Bootstrap.
- Improved the performance of SQL and performed query optimizations.
- Created a back-end payment module using PHP and CakePHP.
- Improved the existing payment modules.
Technologies: Bootstrap, jQuery, CakePHP, MySQL, JavaScript, PHPProject Manager
2013 - 2014ESES Global, Inc.- Designed and implemented an Android app, providing guesthouse information.
- Helped the app succeed as the number one app in the new free app section of Google Play Store.
- Acquired +30,000 users in three months after launch with Facebook marketing.
- Designed and implemented a search engine website providing job information for expatriates living in South Korea.
- Acquired dispersed job information from Korea to give job seekers access to tons of job information with one search.
Technologies: MongoDB, Yii, LAMP, AndroidJava Developer
2012 - 2012Samsung SDS (Contract)- Implemented SAP EP modules reflecting company-wide requirements of Samsung.
- Designed front-end web pages for the responsive web requirements.
- Enabled functionality on all other modern browsers, unlike the previous version which had only been available on IE.
Technologies: Oracle, SAP Enterprise Portal, HTML5, JavaSenior Software Engineer
2010 - 2011Outspark, Inc.- Increased work efficiency of the PM and GM by developing a new CMS for web content management.
- Improved front-end rendering performance by 30% by deploying a new client-side platform for all game websites.
- Improved back-end performance by creating a replacement of the existing server-side platform.
Technologies: MySQL, CodeIgniter, YUI, jQuery, JavaScript, PHPTeam Leader
2008 - 2010G&G Commerce- Designed, developed, and successfully launched an innovative web avatar application on eBay, which displays cyber garments. Users could search for items on the website by mapping cyber garments on an avatar using the application. The company could get paid as an eBay affiliate through this application because this application advertises eBay sellers' items as a search result. This application enables sellers to earn net profits by putting it into their websites and blogs, reflecting customers' needs.
Technologies: MySQL, YUI, JavaScript, PHP, CFront-end Engineer
2007 - 2008Yahoo Korea- Developed various Yahoo Korea portal web pages.
- Designed and implemented games using JavaScript.
- Constructed an intuitive game interface for the Korean market, which resulted in a positive user experience and high user engagement.
Technologies: YUI, JavaScript, PHP