Cross-Chain Lending Protocol

Deposit collateral on one chain, borrow on another. Multi-chain DeFi with unified liquidity — the protocol Aave, Compound, and MakerDAO never built.

On-Chain Proof (Deployed & Verified)

Base Sepolia (OP Stack)

Contract	Address
LendingPool	0x0c528b57...5691
LiquidationEngine	0x47738C17...1c48
CrossChainMessenger	0xd3523B89...8EaA
YieldVault	0xB972CcEc...eDC7
RiskManager	0xF1D3A321...1BE
GovernanceToken	0x44B5914e...aAC3
PriceOracle	0x0457800F...6877

Linea Sepolia (ZK-Rollup)

Contract	Address
LendingPool	0x2AaA42fa...85cC
LiquidationEngine	0x49F22168...6976
CrossChainMessenger	0x77aaA2AB...01D3
YieldVault	0x5c886F28...5B19
RiskManager	0x9ff0C982...4861
GovernanceToken	0x7793F72c...e50A
PriceOracle	0xB48f1eEc...A862

Deployer: 0x7F75bfAfeD5c96584774c7F2Bc33F3bF887BC739

Why This Is Different

Current DeFi lending is siloed per chain:

• Aave on Ethereum ≠ Aave on Base
• Users must bridge, swap, deposit, borrow on each chain separately
• Liquidity is fragmented, capital efficiency is wasted

Cross-Chain Lending Protocol unifies this:

• Deposit ETH on Base → Borrow USDC on Linea (or any supported chain)
• Single position, multi-chain exposure
• Unified interest rates across the entire protocol

Architecture

┌──────────────────────────────────────────────────────────┐
│                  CROSS-CHAIN MESSENGER                   │
│                  (Chainlink CCIP)                        │
└──────────────────────────────────────────────────────────┘
        │              │              │              │
        ▼              ▼              ▼              ▼
   ┌─────────┐   ┌─────────┐   ┌─────────┐   ┌─────────┐
   │  Base   │   │  Linea  │   │  Other  │   │  Other  │
   │ Lending │   │ Lending │   │ Lending │   │ Lending │
   │  Pool   │   │  Pool   │   │  Pool   │   │  Pool   │
   └─────────┘   └─────────┘   └─────────┘   └─────────┘
        │              │              │              │
        └──────────────┴──────────────┴──────────────┘
                              │
                ┌─────────────┼─────────────┐
                ▼             ▼             ▼
          ┌──────────┐ ┌──────────┐ ┌──────────┐
          │ Price    │ │Liquidation│ │  Risk    │
          │ Oracle   │ │  Engine  │ │ Manager  │
          └──────────┘ └──────────┘ └──────────┘

Smart Contracts

LendingPool.sol — Core Lending Engine

• Multi-asset deposit/borrow/repay/withdraw
• Kinked interest rate model (5% base, 20% slope, 150% steep)
• Health factor calculation with 80% LTV / 85% liquidation threshold
• 5% liquidation bonus for liquidators
• Non-reentrant, gas-optimized

CrossChainMessenger.sol — CCIP Integration

• Send/receive cross-chain messages via Chainlink CCIP
• Queue and execute cross-chain actions
• Message timeout protection (30 min default)
• Replay protection (executed messages can't be re-executed)

LiquidationEngine.sol — Automated Liquidations

• Register/remove liquidators
• Auto-trigger on health factor < 0.85
• 0.5% reward + 5% bonus for liquidators
• Cooldown protection (1 min between liquidations)
• Full liquidation history tracking

RiskManager.sol — Protocol-Wide Risk Monitoring

• Per-market risk configurations
• Real-time risk assessment (utilization, APY, reserves)
• Auto circuit breaker for critical alerts
• Emergency market pause
• Protocol health scoring (0-1000)

YieldVault.sol — Auto-Compounding Vault

• Multi-strategy yield aggregation
• Deposit cap enforcement
• Performance fee (2%) + withdrawal fee (0.1%)
• Share-based accounting (ERC4626-style)
• Auto-harvest with configurable interval

GovernanceToken.sol — Protocol Governance

• ERC20 with delegation (Compound-style)
• On-chain proposals with voting
• 100k token threshold to propose
• 400k token quorum requirement
• Vote delegation and power tracking

PriceOracle.sol — Chainlink Price Feeds

• Multi-feed support (AggregatorV3)
• Stale price detection (1 hour threshold)
• Exchange rate calculation
• Governance-controlled feed management

Interest Rate Model

Interest Rate
      │
20% ──┤                          ╱
      │                        ╱
10% ──┤                    ╱
      │                ╱
 5% ──┤────────────╱
      │          ╱
 0% ──┼───────╱─────────────────────
      0%   80% (kink)         100% Utilization

• Base Rate: 5% APR
• Slope 1: 0% → 80% utilization: rate = 5% + 20% × util
• Slope 2: 80% → 100% utilization: rate = 21% + 150% × (util - 80%)

This incentivizes borrowing at healthy utilization while preventing complete capital drain.

Setup

git clone https://github.com/Souravjoy7/cross-chain-lend.git
cd cross-chain-lend
npm install
npx hardhat compile

Deployment

export DEPLOYER_PRIVATE_KEY=0x...
npx hardhat run scripts/deploy.js --network base_sepolia
npx hardhat run scripts/deploy.js --network linea_sepolia

Tech Stack

• Solidity 0.8.24
• Hardhat 3
• OpenZeppelin v5
• Chainlink CCIP + Price Feeds
• Ethers v6

Security Features

• ReentrancyGuard on all state-changing functions
• Health factor checks before borrow
• Liquidation threshold with bonus
• Message timeout + replay protection
• Governance-controlled emergency pause
• Circuit breaker on critical risk events

License

MIT