Kakao

See the following -

The State of Open Source in South Korea

Open source software is growing exponentially all around the world, and South Korea is a vital part of that trend. While most South Korean open source projects don't get the international attention that projects from the Apache Foundation, the Linux Foundation, and similar organizations receive, they are making significant contributions to mobility, artificial intelligence, web technologies, and other areas. Samsung may be the best-known South Korean company working in open source, but Naver, Kakao, Coupang, and others are also writing important open source software and maintaining their projects on GitHub.