One person.
End to end.
I am KC, and KKC Labs is my one person studio in Seoul. I plan, design, build and ship apps and web products by myself. Six of them are running in production right now.
// selected work
Things I built.
Not demos. These are live products with real users. The detailed case studies are in Korean, but the screenshots and stacks read fine either way.
GYMKC
An AI fitness trainer that adjusts weight and rest between every set. The prescription engine is pure TypeScript running on the device, so it keeps working with no connection. React 19, Capacitor on Android and iOS, Cloudflare D1.
Case study (Korean) → personal projectHome monitoring PWA
A parenting app that never uploads its live camera feed to the cloud: an on-site Mac republishes RTSP as low-latency WebRTC, and remote access goes over a private network rather than a public server. Sound-event detection, passkey sign-in, and an always-on tablet kiosk that puts weather, air quality and seasonal appliances on one screen.
Case study (Korean) → planning · build · content pipelineSonetho
A technical blog about AI voice and video in 16 languages. I write one post in Korean and a pipeline translates and localises it into 15 more, all server rendered at the edge so crawlers read it properly.
Case study (Korean) → planning · build · shipFrompter
A teleprompter that scrolls itself by listening to you. Speech recognition tracks where you are in the script, in 17 languages. Phone, keyboard and a second operator can all drive it at once. An Apple Watch remote comes with the iOS app. Camera recording, AI proofreading, offline mode, and a paid tier on the web and the App Store.
Case study (Korean) → planning · build · infrastructureQUICKCUT
A B2B tool for video teams. Transcription, silence removal, style guide compliant subtitles, translation and editor file export in one pipeline. The app and its renders live on one Mac mini in the studio, exposed to the outside only through a Cloudflare Tunnel. Sibling app QUICKAUDIO restores speech and splits dialogue from background audio.
Case study (Korean) → client work · full stackINDISIGN
A signage company site built on Cloudflare Workers with no framework and no build step. It ships with a CMS I wrote for an owner who does not code. This is my first delivered client project.
Case study (Korean) →// how I work
Everything in one head.
When work moves between agencies, time leaks at every handover and the intent gets diluted. I hold the whole thing, from the first sketch to the deploy and whatever breaks afterwards.
I lean on AI tools where they make me faster. The last call and the final polish are still mine.
Practically: Seoul, UTC+9. I work in English by email and async, and I am comfortable reading and writing it. Video calls are possible but slower for me.
// get in touch
> Want to build something together?
Collaboration, a project, or just a question about how something here was built. All welcome.
Or just email [email protected] directly.