ZodiacDrone — I Built an AI-Powered Astrology App ✨🔮

#showdev #nextjs #ai #typescript

Hey folks! 👋

I want to share my journey of building ZodiacDrone — an AI-powered astrology app. I've always been fascinated by the stars, but frustrated by the UX of existing tools. So, I decided to bridge the gap between ancient wisdom and modern AI.

💫 The "Why"

Traditional astrology apps often feel like reading a clinical lab report: "Mars conjunct Saturn in the 12th House." 🤨

Instead of clarity, users get jargon. I wanted to use AI as a Celestial Translator—turning raw planetary data into meaningful, human conversations.

🛠️ The Tech Stack (2026 Edition)

I wanted a stack that balances developer experience with high performance:

Next.js 16 — Leveraging the latest App Router optimizations.
tRPC v11 + Hono — For that sweet, end-to-end type safety.
PostgreSQL + Drizzle ORM — Because Drizzle's DX is unbeatable for relational data.
Better Auth — A solid, modern authentication layer.
Vercel AI SDK + OpenAI — Powering the core "Soul Guide" LLM.
Tailwind CSS 4 — Zero-runtime CSS-in-JS that keeps the UI snappy.

The project is structured as a pnpm monorepo, which makes sharing types between the web app and background workers a breeze.

🔮 The Biggest Challenge: Math > Magic

The hardest part wasn't the AI—it was the Astronomy.

Initially, I thought I could let the LLM handle the calculations. Big mistake. LLMs are notorious for hallucinating coordinates. To get it right, I integrated astronomy-engine.

It's a pure JS library that allows me to calculate exact planetary positions with zero native bindings—perfect for Edge Runtime!

🤖 Architecting the AI Reading

I built a conversational interface that doesn't just "spit out text." Using the Vercel AI SDK, the app streams responses in real-time.

One cool feature: Checkpoint Support. If the user’s connection drops mid-reading, the session state is preserved so they can pick up right where the stars left off.

🎨 Aesthetics as a Feature

As developers, we often forget that UI is part of the value proposition. I obsessed over our Art-grade Share Cards. Using a mix of SVG manipulation and Canvas, we generate social-ready snapshots of a user's "Cosmic Signature." Because if it’s not beautiful, is it even worth sharing?