About

Who

zzinDev is a one-person software studio.

zzinDev LLC is a California limited liability company founded and operated by Hong-Bin Yoon. It exists to build small, useful products — things I'd want to use, built the way I'd want them built.

I'm a software engineer. I've shipped backend systems, mobile apps, and AI tooling. zzinDev is where I focus on products I genuinely care about rather than whichever thing happens to be on a sprint board.

Products

AnimeNuna →

An AI-powered, fully automated anime recap channel. Season-level breakdowns rendered into narrated videos and published on YouTube.

Lessonary →

A lesson-recap and video-sharing app for instructors. Flutter on web and mobile, Firebase backend, Stripe for billing, RevenueCat for mobile IAP. Live at lessonary.zzin.dev.

How things get written

The blog content on zzin.dev is AI-assisted and human-edited. First drafts come from a scripted pipeline that calls Anthropic's Claude language model with structured prompts; every draft is then reviewed and edited by me before it's published. Nothing on the blog ships without human review.

The full editorial process — what human review covers, where the data comes from, how to request a correction — is documented on the Editorial Standards page.

The company

Legal name: zzinDev LLC
Founder: Hong-Bin Yoon
Registered address: 13603 Almond St, Tustin, CA 92782
State of registration: California, USA
Email: hong-bin@zzin.dev

For editorial questions, corrections, or business inquiries, see the Contact page.