Smart cold-chain monitoring with IoT sensors, real-time alerts, and blockchain verification.

Prize Pool

Koilen is an intelligent cold-chain monitoring system that uses wireless IoT sensors to track temperature and humidity in real time and stores every reading on the blockchain for tamper-proof traceability. The platform provides instant alerts when conditions go out of range, a dashboard to visualize sensor data across sites, and automated compliance reports verified on-chain. Our goal is to bring mission-critical reliability—previously accessible only through expensive industrial systems—to food, pharma, logistics, and data-center operators through an affordable, transparent, and auditable solution.
Dual EVVM Deployment - Complete ecosystem mastery through two parallel implementations:
Tech Stack: Solidity 0.8.30 + Foundry + Next.js 15/16 + TypeScript + Wagmi v2 + RainbowKit + Viem
Smart Contracts: Hierarchical structure (Client→Branch→Sensor), variable KOIL economics (0-5 KOIL/event), dual NameService support via constructor injection.
Notable Hacks: 5-layer RPC fallback for 99%+ deployment success Temperature encoding: -5°C = BigInt(-5000000) for int256 compatibility
Dual NameService: Same codebase works with MATE + Custom via address swap Auto event detection: Frontend calculates costs before transaction
Frontends: EVVM Signature Constructor + Koilen Dashboard. Real-time event type detection, color-coded UI, RainbowKit integration. Verified contracts on Etherscan. 8 documentation guides. Production-ready IoT monitoring.

