洪 民憙 (Hong Minhee) 
@hongminhee@hollo.social
I've wanted to build a mixed-script Korean input method for more than ten years, and I finally started building it.
The project is called Bibim. Korean, Japanese, and Chinese share a lot of Sino-derived words written with Chinese characters, even when the readings differ. Bibim uses those characters as the bridge: if you're writing Japanese and can't remember the Japanese reading of 博物館 (“museum”), you can type the Korean reading (bangmulgwan) instead, and it will recover the characters for you.
I finished the design doc today. If you're into CJK writing systems, East Asian languages, or input method development, I'd love feedback.