Hi. I'm the developer behind Cheonmyeongdang (천명당) — an AI-powered Korean Saju engine that I'm building from a small studio in Gyeongju, the 1,000-year-old former capital of Korea. No team. No VC. Just me, an API key, and a lot of classical Saju textbooks.
Updated manually each month. Nothing fancy here yet — that's the point. If you're watching an indie project from day zero, you're seeing the truth, not a polished pitch deck.
Saju (사주팔자, Four Pillars of Destiny) is a 1,000-year-old Korean system that maps your birth moment to 8 stem-branch pillars. It is, in my opinion, the most rigorous fortune-telling framework that ever existed — closer to mathematics than to mysticism.
But the global audience can't access it. Western astrology has Co-Star and The Pattern. Bazi (the Chinese cousin) has a few apps. Saju? Almost nothing in English. The few that exist are either pure generic-AI wrappers (which hallucinate your hour pillar 30% of the time) or Korean-only services that won't accept a foreign credit card.
The bet: Korean traditional wisdom + a deterministic 8-pillar engine + AI for interpretation + 4-language UI + PayPal global checkout. Make 1,000 years of Korean knowledge readable by anyone in the world with a birth date.
The 8-pillar calculation is done by classical algorithms, validated against printed Korean reference charts. Our AI only handles the interpretation layer — exactly how a human Korean reader would explain your chart in plain language.
Full Saju calculation, daily fortune, and one AI Q&A round are free forever. Premium ($7.99 one-time or $39.99/mo) unlocks unlimited Q&A, monthly fortune, compatibility, and a 30-page PDF report.
Every page is rewritten natively in 4 languages — not machine-translated. The English version is not a translation of the Korean; the Japanese version is not a translation of the English. Each has its own copy, examples, and cultural framing.
You don't lose anything by trying us. Cancel anytime, and get a refund on any premium reading within 7 days if the report has not been downloaded.
Cheonmyeongdang is the first SaaS product under KunStudio, a one-person studio I started in 2026 in Gyeongju. The thesis is simple: take traditions that are deeply Korean — Saju, Korean tax law, Korean travel knowledge, Korean wisdom — and rebuild them as global SaaS with AI as the interpreter layer.
Western astrology uses 12 sun signs. Saju uses 60 stem-branch pairs across 4 pillars, which means 12,960,000 possible birth-time combinations. That's roughly 60× more granularity than your zodiac sun sign.
It's not magic. It's a 1,000-year-old taxonomy of human archetypes, refined by Korean scholars who treated it as a serious discipline. AI can finally make it accessible without losing the rigor.
I share lessons, mistakes, and revenue numbers as openly as I reasonably can. If you want to follow along — or if you have a question about indie SaaS, Korean traditional knowledge, or AI-augmented domain products — the contact email is below.