Aave V3 (aave-v3)

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When to use it

• Earn interest on an asset the market lists, or borrow one against everything you supplied in that market. One Pool per market holds every reserve.
• Choose it over Compound V3 when you need to borrow more than one asset against shared collateral, and over Morpho Blue when you want one shared market rather than isolated ones.

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Pitfalls for a program

• supply pulls the asset with transferFrom: approve the Pool for exactly the amount first.
• onBehalfOf receives the aTokens, and with them the position. Every call comes from the Pot, so pot there keeps the position in the Pot, not in the user’s wallet; choose which, and pass the wallet as a main parameter to give it to the user. A position in the wallet is the wallet’s: withdraw burns the caller’s aTokens, so a later cook withdraws it only once they are back in the Pot, and borrows against it only with the wallet’s credit delegation.
• The aToken minted to onBehalfOf is rebasing: its balance grows with interest, so measure it as a delta, not as the amount supplied.
• A reserve can be frozen, paused or at its supply cap, and then supply reverts.
• Borrowing needs collateral and keeps the position’s health factor (from getUserAccountData, scaled by 1e18) above 1; below it, anyone may liquidate.
• withdraw with ~0 withdraws everything; it reverts if that would leave a borrow undercollateralized.
• flashLoanSimple calls back a receiver contract, which a Sauce program cannot be.

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In a Sauce program

function main(onBehalfOf: Address, amount: Uint256) {
  USDC.approve(AaveV3.Pool, amount);
  AaveV3.Pool.supply(USDC, amount, onBehalfOf, 0);
  const account = AaveV3.Pool.getUserAccountData(onBehalfOf);
  require(account.totalCollateralBase > 0, "nothing supplied");
}

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Notes

• interestRateMode: 1 = stable (deprecated on most markets), 2 = variable
• referralCode is always 0 (referral program inactive)
• V3 introduced efficiency mode (eMode) for correlated assets, isolation mode for new assets, and siloed borrowing
• All supply/repay operations require prior ERC-20 approval to the Pool address
• healthFactor < 1e18 means position is liquidatable

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Its names in a program

function main() {
  // Ethereum's pool, `0x87870Bca3F3fD6335C3F4ce8392D69350B4fA4E2`.
  require(AaveV3.Pool != 0);
}

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Deployments

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ABI

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PoolABI

• supply(address asset, uint256 amount, address onBehalfOf, uint16 referralCode)
• withdraw(address asset, uint256 amount, address to) returns (uint256)
• borrow(address asset, uint256 amount, uint256 interestRateMode, uint16 referralCode, address onBehalfOf)
• repay(address asset, uint256 amount, uint256 interestRateMode, address onBehalfOf) returns (uint256)
• flashLoanSimple(address receiverAddress, address asset, uint256 amount, bytes params, uint16 referralCode)
• liquidationCall(address collateralAsset, address debtAsset, address user, uint256 debtToCover, bool receiveAToken)
• getUserAccountData(address user) view returns (uint256 totalCollateralBase, uint256 totalDebtBase, uint256 availableBorrowsBase, uint256 currentLiquidationThreshold, uint256 ltv, uint256 healthFactor)

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Next steps

• Protocols: the other protocols, by what they do.
• Protocols and tokens: calling a contract by its namespace, or through its ABI.
• Glossary: the words these pages use, in plain terms.