Multi-Strategy Yield Vault

An ERC-4626 tokenized vault that allocates deposits across multiple DeFi yield strategies (Aave V3, Compound V3, and extensible to any protocol).

Architecture

Depositors ──> MultiStrategyVault (ERC-4626) ──> Strategy A (Aave V3)
                     |                          ──> Strategy B (Compound V3)
                     |                          ──> Strategy C (custom)
                     v
              Vault Shares (msUSDC)

Core contracts:

Contract	Description
MultiStrategyVault	ERC-4626 vault with timelocked strategy management, rebalancing, and performance fees
AaveV3Strategy	Deposits into Aave V3 lending pool, yield via aToken rebasing
CompoundV3Strategy	Supplies to Compound V3 (Comet) markets
IStrategy	Interface for building custom yield strategies

Security Features

• Timelocked strategy additions -- 2-day delay between proposal and execution prevents instant rug
• Allocation caps -- Total strategy allocation cannot exceed 100% (10,000 bps)
• Reentrancy protection -- All state-changing externals use OpenZeppelin ReentrancyGuard
• Emergency withdrawal -- Owner can pull all funds from all strategies; tolerates individual strategy failures
• Pausable -- Deposits can be paused while withdrawals remain active
• Performance fee cap -- Maximum 20% (2,000 bps), enforced at contract level

Building

forge build

Testing

forge test          # Run all tests
forge test -vvv     # Verbose output with traces
forge test --gas-report  # Gas usage report

28 tests including:

• Unit tests for deposits, withdrawals, strategy management
• Access control tests
• Emergency scenario tests (reverting strategies)
• Fuzz tests for deposit/redeem invariants

Deployment

# Set environment
export PRIVATE_KEY=0x...
export RPC_URL=https://eth-mainnet.g.alchemy.com/v2/...

# Deploy
forge script script/Deploy.s.sol --rpc-url $RPC_URL --broadcast

Adding a Custom Strategy

Implement IStrategy:

contract MyStrategy is IStrategy {
    function asset() external view returns (IERC20);
    function totalAssets() external view returns (uint256);
    function deposit(uint256 amount) external;
    function withdraw(uint256 amount) external returns (uint256);
    function harvest() external returns (uint256);
}

Then propose it via the vault:

vault.proposeStrategy(address(myStrategy));
// Wait 2 days...
vault.executeAddStrategy(3000); // 30% allocation

License

MIT