I'm 16, self-taught, and I built a fake transfer receipt detector for Nigerian businesses

Jonathan, a 16-year-old self-taught developer from Bauchi, Nigeria, built NaijaStack, a free business automation tool for Nigerian SMEs whose AI Fake Transfer Detector scans payment receipts from services like OPay, PalmPay, Moniepoint and GTBank to flag forgeries such as edited fonts, wrong session IDs and doctored amounts. The PWA, built with vanilla JavaScript, Firebase Firestore and Google Gemini via Netlify Functions, also offers order tracking, stock management, expense tracking and a WhatsApp-integrated AI business assistant. Jonathan is seeking feedback on Firestore security rules, receipt-detection prompt engineering and acquiring his first users.

Hi Dev.to 👋 I'm Jonathan, 16, from Bauchi, Nigeria. Self-taught developer. This is my first real product. The Problem I'm Solving Fake bank transfer receipts are destroying Nigerian small businesses. A buyer sends a screenshot of a "successful transfer" — it looks 100% real. The vendor ships the goods. The money never lands. The vendor loses the goods AND the money, with zero recourse. I've seen one of these fake receipts myself. If a vendor wasn't paying attention, they'd be scammed in 5 seconds. What I Built NaijaStack — a free business automation tool for Nigerian SMEs. Key features: - AI Fake Transfer Detector — scans payment receipts OPay, PalmPay, Moniepoint, GTBank, etc. and flags fakes: edited fonts, wrong session IDs, doctored amounts - AI Magic Fill — type "Emeka bought 2 shirts for 15k" and the form fills itself - Order tracking — New → In Progress → Ready → Paid - Stock management — auto-decrements when you sell - Expense tracker + 7-day P&L dashboard - WhatsApp receipts, reminders, and rider dispatch - AI Business Assistant — ask "how much profit did I make this week?" and get a real answer Tech Stack - Vanilla JS no framework - Firebase Firestore + Auth - Google Gemini API via Netlify Functions API key never exposed - PWA installable, works offline - Hosted on Netlify What I Learned Building This 1. Structure over features. My first version had nested event listeners that duplicated orders. Lesson: keep functions clean. 2. Security is not optional. I moved my Gemini API key to a Netlify Function after realizing it was exposed in the browser. 3. Small details matter. Toasts, skeleton loaders, an onboarding tour — these took 10% of the time and made a 90% difference in feel. What I Need Help With - Security — I'm learning this as I go. Any tips on Firestore rules or API safety? - AI prompt engineering — how would you improve the fake receipt detection? - Getting my first users — I have zero. Advice welcome. Try It It's free during beta, no card: https://naijastack.netlify.app https://naijastack.netlify.app Feedback welcome — good or bad. I'd rather know what's broken than ship something mediocre. — Jonathan