ERC4626Strategy

Git Source

Inherits: BaseHealthCheck

Title: ERC4626Strategy

Author: Golem Foundation

Yield-donating strategy that compounds rewards from any ERC4626-compliant vault

Deposits assets into an ERC4626 vault to earn yield which is donated via BaseHealthCheck's profit minting mechanism YIELD FLOW:

1. Deposits assets into ERC4626 vault
2. Vault generates yield through its specific strategies
3. On report, profit is minted as shares to donation address COMPATIBILITY:

• Works with any standard ERC4626 vault (Spark, Yearn v3, etc.)
• Vault must have manipulation-resistant convertToAssets implementation INTEGRATOR WARNING — per-target audit required: ERC-4626 compliance is a spec-level claim. Several production vaults that advertise conformance still have edge cases that break the semantics this strategy relies on (in particular availableDepositLimit / availableWithdrawLimit, which trust the target vault's maxDeposit / maxWithdraw at face value):
• MetaMorpho-style vaults can return maxDeposit == 0 as a normal operating state while their curator reallocates liquidity across markets. Deposits must be expected to fail with "deposit more than max" during those windows even though the strategy code is correct.
• Euler-V2-style vaults' max* values can be inaccurate once hooks are installed on the vault — the vault's own documentation notes that "some hook configurations may cause the vault to not be fully ERC-4626 compliant". Every target vault MUST be studied and audited individually before this strategy is deployed against it. Do not treat ERC-4626 conformance as a blanket security guarantee.

Notes:

• security-contact: [email protected]

• security: ERC4626 vault convertToAssets must be manipulation-resistant

• security: Target vault must be audited individually before deployment

Target vault review required

ERC-4626 compatibility alone is not enough. Each target vault needs protocol-specific review before use, especially around previews, fees, liquidity, and share inflation behavior.

Quick Start - What Matters Most

This is the generic ERC-4626 yield-donating adapter. In .6 it uses exact per-deposit approvals, reverts when a deposit mints zero shares, clears allowances after deposit, preserves unlimited target-vault capacity sentinels, and reports assets with previewRedeem.

State Variables

targetVault

Address of the ERC4626 vault this strategy deposits into

Must implement IERC4626 interface and use the same asset as this strategy

address public immutable targetVault

Functions

constructor

Initializes the ERC4626 strategy

Validates asset matches target vault's asset. Approval is issued per-deposit inside _deployFunds and explicitly cleared after the target vault call, so no standing allowance against the external (upgradeable) target vault exists between calls.

constructor(
    address _targetVault,
    address _asset,
    string memory _name,
    string memory _symbol,
    address _management,
    address _keeper,
    address _emergencyAdmin,
    address _donationAddress,
    bool _enableBurning,
    address _tokenizedStrategyAddress
)
    BaseHealthCheck(
        _asset,
        _name,
        _symbol,
        _management,
        _keeper,
        _emergencyAdmin,
        _donationAddress,
        _enableBurning,
        _tokenizedStrategyAddress
    );

Parameters

Name	Type	Description
_targetVault	address	Address of the ERC4626 vault this strategy deposits into
_asset	address	Address of the underlying asset (must match target vault's asset)
_name	string	Strategy display name (e.g., "Octant ERC4626 Strategy")
_symbol	string	Strategy token symbol (e.g., "osERC4626")
_management	address	Address with management permissions
_keeper	address	Address authorized to call report() and tend()
_emergencyAdmin	address	Address authorized for emergency shutdown
_donationAddress	address	Address receiving minted profit shares
_enableBurning	bool	True to enable loss protection via share burning
_tokenizedStrategyAddress	address	Address of TokenizedStrategy implementation contract

availableDepositLimit

Returns maximum additional assets that can be deposited

Queries target vault's maxDeposit and subtracts idle balance

function availableDepositLimit(
    address /*_owner*/
)
    public
    view
    override
    returns (uint256);

Returns

Name	Type	Description
<none>	uint256	limit Maximum additional deposit amount in asset base units

availableWithdrawLimit

Returns maximum assets withdrawable without expected loss

Sums idle balance and target vault's maxWithdraw

function availableWithdrawLimit(
    address /*_owner*/
)
    public
    view
    override
    returns (uint256);

Returns

Name	Type	Description
<none>	uint256	limit Maximum withdrawal amount in asset base units

_deployFunds

Deposits idle assets into ERC4626 vault

function _deployFunds(uint256 _amount) internal override;

Parameters

Name	Type	Description
_amount	uint256	Amount of assets to deploy in asset base units

_freeFunds

Withdraws assets from ERC4626 vault

Note: security: withdraw returns shares burned, not assets received. TokenizedStrategy._withdraw measures the post-call asset balance and applies the caller's max-loss limit.

function _freeFunds(uint256 _amount) internal override;

Parameters

Name	Type	Description
_amount	uint256	Amount of assets to withdraw in asset base units

_emergencyWithdraw

Emergency withdrawal after strategy shutdown

function _emergencyWithdraw(uint256 _amount) internal override;

Parameters

Name	Type	Description
_amount	uint256	Amount of assets to withdraw in asset base units

_harvestAndReport

Reports current total assets under management

function _harvestAndReport() internal view override returns (uint256 _totalAssets);

Returns

Name	Type	Description
_totalAssets	uint256	Sum of target vault value and idle assets in asset base units