SACCO Digital Wallet

Project Overview

The SACCO Digital Wallet is a mobile-first fintech platform designed for farmers in Kyenjojo, Uganda. It enables farmers to register, verify their farms via GPS, access savings and loan services, and get climate intelligence data to improve agricultural decision-making.

The platform was migrated from Supabase to Firebase for its backend, using Firestore for data storage and Firebase Auth for user management. The offline-first design ensures farmers in areas with poor connectivity can still access core features.

Key Features

• Offline-first architecture optimized for low-end Android devices
• Firebase Authentication and Firestore database
• GPS-based farm boundary mapping and verification
• Shoelace formula geometric acreage calculation
• NASA POWER API integration for climate and weather data
• Agricultural Intelligence module for crop recommendations
• Multi-language support (Runyoro, Luganda, English)
• Admin audit module with vendor verification and financial risk scoring
• Automated PostgreSQL triggers for user registration lifecycle (profiles, wallets, farm_records)
• Wallet and savings management with loan tracking

Technology Stack

The Challenge

Farmers in rural Uganda needed a financial tool that works on low-end Android devices with intermittent connectivity. Key challenges:

• Building an offline-first app that syncs when connectivity returns
• Integrating NASA POWER climate data for agricultural intelligence
• GPS-based farm verification to prevent fraud in loan applications
• Calculating farm acreage from GPS polygon boundaries
• Supporting local languages (Runyoro/Luganda) for rural farmers
• Admin tools for auditing vendor claims and financial risk assessment

The Solution

We built the platform with Firebase for real-time data sync and offline persistence. The Shoelace formula calculates acreage from GPS coordinates mapped by farmers walking their boundaries. The NASA POWER API provides climate insights for crop planning.

The admin audit module flags any farm where self-reported acreage differs from polygon-calculated area by more than 15%, preventing loan fraud. The platform supports three languages and is optimized for devices with as little as 1GB RAM.

Results

• Farmers can register and verify farms entirely from their phones
• Climate data helps farmers make informed planting decisions
• GPS verification reduces loan fraud by validating actual farm sizes
• Offline-first design works in areas with no internet
• Admin dashboard provides real-time financial risk monitoring