| name | Aave V3 Architecture |
| description | This skill should be used when the user asks about "Aave V3 architecture", "Pool contract", "PoolAddressesProvider", "PoolConfigurator", "Aave lending", "Aave borrowing", or needs a high-level understanding of how Aave V3 works. |
| version | 0.1.0 |
Aave V3 Architecture
Aave V3 is a decentralized non-custodial lending protocol where users can supply assets to earn interest and borrow against collateral. This skill provides a high-level overview of the protocol architecture.
Overview
┌──────────────────────────────────────────────────────────────┐
│ AAVE V3 ARCHITECTURE │
├──────────────────────────────────────────────────────────────┤
│ │
│ ┌─────────────────────────────────────────────────────────┐ │
│ │ PoolAddressesProvider │ │
│ │ Central registry for all protocol contracts │ │
│ └─────────────────────────────────────────────────────────┘ │
│ │ │
│ ┌──────────────────────┼──────────────────────┐ │
│ ▼ ▼ ▼ │
│ ┌─────────┐ ┌─────────────┐ ┌───────────┐ │
│ │ Pool │◄────────►│PoolConfig- │ │ ACLManager│ │
│ │ │ │ urator │ │ │ │
│ └────┬────┘ └─────────────┘ └───────────┘ │
│ │ │
│ │ manages │
│ ▼ │
│ ┌─────────────────────────────────────────────────────────┐ │
│ │ Reserves (Assets) │ │
│ │ ┌─────────┐ ┌─────────┐ ┌─────────┐ ┌─────────┐ │ │
│ │ │ aToken │ │ Variable│ │ Interest│ │ Oracle │ │ │
│ │ │ │ │DebtToken│ │RateStrat│ │ │ │ │
│ │ └─────────┘ └─────────┘ └─────────┘ └─────────┘ │ │
│ └─────────────────────────────────────────────────────────┘ │
│ │
└──────────────────────────────────────────────────────────────┘
Core Components
PoolAddressesProvider
The central registry that stores addresses of all protocol contracts for a specific market.
interface IPoolAddressesProvider {
function getPool() external view returns (address);
function getPoolConfigurator() external view returns (address);
function getPriceOracle() external view returns (address);
function getACLManager() external view returns (address);
function getACLAdmin() external view returns (address);
function getPriceOracleSentinel() external view returns (address);
function getPoolDataProvider() external view returns (address);
// Generic address getter for custom identifiers
function getAddress(bytes32 id) external view returns (address);
}
Pool
The main entry point for user interactions. All supply, borrow, repay, and withdraw operations go through the Pool.
interface IPool {
// Core operations
function supply(address asset, uint256 amount, address onBehalfOf, uint16 referralCode) external;
function withdraw(address asset, uint256 amount, address to) external returns (uint256);
function borrow(address asset, uint256 amount, uint256 interestRateMode, uint16 referralCode, address onBehalfOf) external;
function repay(address asset, uint256 amount, uint256 interestRateMode, address onBehalfOf) external returns (uint256);
// Collateral management
function setUserUseReserveAsCollateral(address asset, bool useAsCollateral) external;
// Liquidation
function liquidationCall(address collateralAsset, address debtAsset, address user, uint256 debtToCover, bool receiveAToken) external;
// Flash loans
function flashLoan(address receiverAddress, address[] calldata assets, uint256[] calldata amounts, uint256[] calldata interestRateModes, address onBehalfOf, bytes calldata params, uint16 referralCode) external;
function flashLoanSimple(address receiverAddress, address asset, uint256 amount, bytes calldata params, uint16 referralCode) external;
// eModes
function setUserEMode(uint8 categoryId) external;
function getUserEMode(address user) external view returns (uint256);
// Account data
function getUserAccountData(address user) external view returns (
uint256 totalCollateralBase,
uint256 totalDebtBase,
uint256 availableBorrowsBase,
uint256 currentLiquidationThreshold,
uint256 ltv,
uint256 healthFactor
);
}
PoolConfigurator
Admin contract for configuring reserves and protocol parameters.
interface IPoolConfigurator {
// Reserve initialization
function initReserves(ConfiguratorInputTypes.InitReserveInput[] calldata input) external;
// Reserve configuration
function setReserveBorrowing(address asset, bool enabled) external;
function configureReserveAsCollateral(address asset, uint256 ltv, uint256 liquidationThreshold, uint256 liquidationBonus) external;
function setReserveFreeze(address asset, bool freeze) external;
function setReservePause(address asset, bool paused) external;
function setReserveFactor(address asset, uint256 newReserveFactor) external;
// Caps
function setBorrowCap(address asset, uint256 newBorrowCap) external;
function setSupplyCap(address asset, uint256 newSupplyCap) external;
// eModes
function setEModeCategory(uint8 categoryId, uint16 ltv, uint16 liquidationThreshold, uint16 liquidationBonus, string calldata label) external;
}
ACLManager
Access control manager for protocol roles.
interface IACLManager {
function isPoolAdmin(address admin) external view returns (bool);
function isEmergencyAdmin(address admin) external view returns (bool);
function isRiskAdmin(address admin) external view returns (bool);
function isFlashBorrower(address borrower) external view returns (bool);
function isBridge(address bridge) external view returns (bool);
function isAssetListingAdmin(address admin) external view returns (bool);
}
Reserve Data Structure
Each asset listed on Aave has associated reserve data:
struct ReserveData {
// Configuration stored as bitmap
ReserveConfigurationMap configuration;
// Indexes (in ray - 27 decimals)
uint128 liquidityIndex; // Supply index for interest accrual
uint128 variableBorrowIndex; // Borrow index for interest accrual
// Current rates (in ray)
uint128 currentLiquidityRate; // Current supply APY
uint128 currentVariableBorrowRate; // Current borrow APY
// Deficit tracking (V3.3)
uint128 deficit;
// Timestamps
uint40 lastUpdateTimestamp;
uint40 liquidationGracePeriodUntil;
// Token addresses
uint16 id;
address aTokenAddress;
address variableDebtTokenAddress;
address interestRateStrategyAddress;
// Accounting
uint128 accruedToTreasury; // Fees accumulated for treasury
uint128 unbacked; // Unbacked aTokens (bridging)
uint128 isolationModeTotalDebt; // Debt in isolation mode
uint128 virtualUnderlyingBalance; // Virtual accounting balance
}
Key Concepts
Interest Rate Model
Aave uses a variable interest rate model:
┌──────────────────────────────────────────────────────────────┐
│ INTEREST RATE CURVE │
├──────────────────────────────────────────────────────────────┤
│ │
│ Rate │ ╱ │
│ │ ╱ │
│ │ ╱ Slope2 │
│ │ ╱ │
│ │ ╱───────╱ │
│ │ ╱ Slope1 │
│ │ ╱ │
│ │ Base Rate ╱ │
│ └───────────────┼─────────────────────────────────── │
│ │ │
│ Optimal │
│ Utilization │
│ │
│ Utilization = Total Debt / (Virtual Balance + Total Debt) │
│ │
└──────────────────────────────────────────────────────────────┘
Loan-to-Value (LTV) and Liquidation
- LTV: Maximum borrowing power as percentage of collateral
- Liquidation Threshold (LT): When health factor drops below 1, liquidation is possible
- Liquidation Bonus (LB): Incentive for liquidators (extra collateral received)
- Health Factor:
HF = Σ(Collateral × LT) / Total Debt
Virtual Accounting (V3.1+)
Aave V3.1+ tracks virtual balances to protect against donation attacks:
// Instead of checking actual token balance:
// balanceOf(aToken)
// Aave uses virtual balance tracking:
virtualUnderlyingBalance += amountSupplied;
virtualUnderlyingBalance -= amountWithdrawn;
eModes (Efficiency Modes)
Allow higher LTV for correlated assets:
struct EModeCategory {
uint16 ltv; // Higher LTV for correlated assets
uint16 liquidationThreshold;
uint16 liquidationBonus;
uint128 collateralBitmap; // Which assets can be collateral
uint128 borrowableBitmap; // Which assets can be borrowed
string label;
}
Protocol Flow
Supply Flow
User → Pool.supply() → SupplyLogic.executeSupply()
1. Update reserve indexes
2. Transfer underlying to aToken
3. Mint aTokens to user
4. Update virtual balance
5. Update interest rates
Borrow Flow
User → Pool.borrow() → BorrowLogic.executeBorrow()
1. Validate health factor will remain >= 1
2. Update reserve indexes
3. Mint debt tokens to user
4. Transfer underlying to user
5. Update interest rates
Liquidation Flow
Liquidator → Pool.liquidationCall() → LiquidationLogic.executeLiquidationCall()
1. Verify user health factor < 1
2. Calculate debt to cover and collateral to receive
3. Burn debt tokens
4. Transfer collateral to liquidator (+ bonus)
5. Update interest rates
Version Features
| Version | Key Features |
|---|
| V3.0 | eModes, isolation mode, siloed borrowing |
| V3.1 | Virtual accounting, stateful interest rates, liquidation grace period |
| V3.2 | Liquid eModes, stable rate deprecation |
| V3.3 | Deficit tracking, liquidation optimizations |
Skills Reference
| Skill | Description |
|---|
aave-v3-pool | Core Pool operations (supply, borrow, repay, withdraw) |
aave-v3-tokens | aTokens and Variable Debt Tokens |
aave-v3-configuration | Reserve configuration and interest rate strategies |
aave-v3-emodes | Efficiency Modes for correlated assets |
aave-v3-flash-loans | Flash loan functionality |
aave-v3-stata-token | ERC4626 wrapper for aTokens |
Reference Files
src/contracts/protocol/pool/Pool.sol - Main Pool contractsrc/contracts/protocol/pool/PoolConfigurator.sol - Configuration contract@crane/contracts/external/aave-v3-origin/contracts/protocol/libraries/types/DataTypes.sol - Core data structures@crane/contracts/external/aave-v3-origin/contracts/interfaces/IPool.sol - Pool interfacesrc/contracts/interfaces/IPoolAddressesProvider.sol - Registry interface
