YSUSU digitizes traditional African savings circles using smart contracts on Hedera. Deployed on testnet with functional web interface and verified smart contracts.
# YSUSU — Hedera-Powered Rotating Savings Circles & Prediction Games
YSUSU is a blockchain implementation of rotating savings and credit associations (ROSCAs) — known as susu in West Africa, tontines in Francophone regions, and chamas in East Africa. It combines:
- Smart contracts for automated contribution tracking and payouts on Hedera testnet
- Consensus-based prediction games for member engagement between rounds
- Next.js web application with WalletConnect integration for HashPack/Blade wallets
- PostgreSQL backend for user data and transaction history
- Direct HBAR transfers via `payable` Solidity functions
This README emphasizes Hedera capabilities to align with Hedera Africa Hackathon 2025 requirements.
## Architecture
```
Traditional ROSCA Flow:
10 members → $100/month each → One member receives $1000 each month → After 10 months, everyone has saved and received $1000
YSUSU Smart Contract Flow:
Members → contribute() with HBAR → Contract tracks rounds → Auto-distribute to scheduled member
↓
Prediction games (10% of pot) keep members engaged between rounds
```
**Deployed Contracts on Hedera Testnet:**
- SusuCircleHederaNative: `0xAf238d3f81773C42b6F4212034A8a735Cd18cbC5`
- PredictionGame: `0x4eE78CE3472a2D6Be52D95B48421933A45739DE7`
- SusuCircleV2Factory: `0xa31B6423587810C2264Ec06fF3b028D6359fbd2c`
## Why Hedera for YSUSU
- **Low, predictable fees**: ~$0.0001 per transaction vs $0.50-$5 on other EVM chains. Critical for small-value contributions ($10-$50) common in informal savings groups.
- **Fast finality**: 3-5 second confirmation enables instant verification during in-person group meetings.
- **EVM compatibility**: Solidity contracts deploy with minimal adjustments (tinybar denomination handling).
- **Carbon-negative network**: Aligns with community-focused financial inclusion mission.
- **Future HTS/HCS potential**: Hedera Token Service for fractional savings tokens, Hedera Consensus Service for dispute resolution logs (not yet implemented). …