TANK
APP
Type
Personal SaaS Project
Role
Full-Stack / Founding Engineer
Year
2024
THE BRIEF
A fuel price comparison SaaS for Germany — built to see how far you can take AI-assisted development in a real project with payments, user accounts, and live external data.
Uses the Tankerkönig API for real-time E5, E10 and Diesel prices. Users can search by location, pin favourites, log fill-ups in the Tankbuch, and set price alerts — all gated behind a Stripe subscription model.
MAP + LIVE PRICES
STRIPE SAAS
WHAT IT DOES
Map & Price View
Interactive Leaflet map powered by OpenStreetMap. Search by location or radius. Stations marked with live prices — cheapest highlighted in green. Super E5, E10, Diesel.
Tankbuch
Log every fill-up
Price Alerts
ADMIN PANEL + KPIs
STACK
Built with Next.js 16 App Router and Bun as the runtime. TypeScript throughout. Tailwind CSS v4 for styling, NextAuth v5 for credentials-based auth, and SQLite (better-sqlite3) to keep the data layer simple and self-hosted.
Stripe handles the subscription lifecycle — checkout, webhook events, and tier upgrades. Deployment via a Linux server with nginx reverse proxy and a systemd service managed by Bun.