ConvexUSDTCrvUSDStrategy

Overview

The ConvexUSDTCrvUSDStrategy contract is a strategy that supplies USDT into the crvUSD-USDT pool in Curve on Polygon, then stakes the curve LP tokens in Convex to maximize yield. It manages conversions between USDT and other tokens using Curve's AtriCrypto zapper.

Constants

address public constant crvUsd = CRV_USD_POLYGON;                                 // CRVUSD token address
address public constant wpol = WPOL_POLYGON;                                      // Wrapped MATIC address
address public constant crv = CRV_POLYGON;                                        // CRV token address
address public constant usdt = USDT_POLYGON;                                      // USDT token address
uint256 public constant CRVUSD_USDT_CONVEX_POOL_ID = CRVUSD_USDT_CONVEX_POOL_ID_POLYGON;  // Convex pool ID
IConvexBoosterPolygon public constant convexBooster = IConvexBoosterPolygon(CONVEX_BOOSTER_POLYGON);  // Convex booster
ICurveAtriCryptoZapper constant zapper = ICurveAtriCryptoZapper(CURVE_AAVE_ATRICRYPTO_ZAPPER_POLYGON);  // Curve zapper

State Variables

IRouter public router;                           // Router for swaps
ICurveLpPool public curveLpPool;                // Main Curve pool

Functions

Initialization Functions

constructor

constructor() initializer

Empty constructor marked as initializer.

initialize

function initialize(
    IMaxApyVault _vault,
    address[] calldata _keepers,
    bytes32 _strategyName,
    address _strategist,
    ICurveLpPool _curveLpPool,
    IRouter _router
) public initializer

Initializes the strategy with required components.

Parameters:

• _vault: MaxApy vault address

• _keepers: Array of keeper addresses

• _strategyName: Name of the strategy

• _strategist: Strategist address

• _curveLpPool: Curve LP pool address

• _router: Router address for swaps

Core Functions

_invest

function _invest(uint256 amount, uint256 minOutputAfterInvestment) internal override returns (uint256)

Invests assets through:

1. Converting USDCe to USDT via zapper

2. Adding USDT to crvUSD-USDT pool

3. Staking LP tokens in Convex

Parameters:

• amount: Amount to invest

• minOutputAfterInvestment: Minimum expected LP tokens

Returns:

• Amount of tokens received

_divest

function _divest(uint256 amount) internal override returns (uint256)

Withdraws assets through:

1. Withdrawing from Convex

2. Removing liquidity from Curve

3. Converting USDT to USDCe via zapper

Parameters:

• amount: LP tokens to divest

Returns:

• Amount received after withdrawals and conversions

_unwindRewards

function _unwindRewards(IConvexRewardsPolygon rewardPool) internal override

Claims and converts rewards:

1. Claims CRV rewards

2. Swaps CRV through multiple hops

3. Converts crvUSD through Curve pool

Parameters:

• rewardPool: Convex rewards pool

Internal View Functions

_convertUsdtToUsdce

function _convertUsdtToUsdce(uint256 usdtAmount) internal view returns (uint256)

Converts USDT to USDCe using zapper.

Parameters:

• usdtAmount: USDT amount

Returns:

• Equivalent USDCe amount

_convertUsdceToUsdt

function _convertUsdceToUsdt(uint256 usdceAmount) internal view returns (uint256)

Converts USDCe to USDT using zapper.

Parameters:

• usdceAmount: USDCe amount

Returns:

• Equivalent USDT amount

_lpValue

function _lpValue(uint256 lp) internal view override returns (uint256)

Calculates underlying value of LP tokens.

Parameters:

• lp: LP token amount

Returns:

• USDCe value

_lpForAmount

function _lpForAmount(uint256 amount) internal view override returns (uint256)

Calculates LP tokens needed for amount.

Parameters:

• amount: USDCe amount

Returns:

• Required LP tokens

_estimatedTotalAssets

function _estimatedTotalAssets() internal view override returns (uint256)

Calculates total strategy value including conversions.

Returns:

• Total value in USDCe

_lpPrice

function _lpPrice() internal view override returns (uint256)

Returns Curve LP token price.

_crv

function _crv() internal pure override returns (address)

Returns CRV token address.

_crvUsdBalance

function _crvUsdBalance() internal view returns (uint256)

Returns strategy's crvUSD balance.

_simulateHarvest

function _simulateHarvest() public override

Simulates harvest operation and reverts with simulation data.