Fees

Performance Fee

Kana charges a 10% performance fee on harvested yield only. There are no deposit fees, withdrawal fees, or management fees.

How It Works

When the keeper bot calls harvestWithSlippage():

1. Strategy claims rewards from all protocols (Yei, Takara, Morpho via Merkl)
2. Swaps reward tokens to USDC with slippage protection (reverts if price manipulated)
3. Vault calculates the yield earned since last harvest
4. 10% of the yield is minted as additional kUSDC shares to the fee recipient
5. The remaining 90% accrues to depositors via increased share value

Slippage protection: The keeper calculates fair prices off-chain and passes minimum output amounts to the harvest function. If the actual swap output is less than expected (e.g., due to MEV attack), the transaction reverts and no fees are taken.

Example

	Amount
USDC in vault	100,000
Yield earned (1 week)	$200
Performance fee (10%)	$20
Net yield to depositors	$180
Effective depositor APY	~9.36% (if gross APY is 10.4%)

Key Properties

Property	Value
Fee type	Performance only
Current rate	10%
Maximum rate	20% (hardcoded cap)
Deposit fee	None
Withdrawal fee	None
Management fee	None
Fee recipient	Configurable address

Why Performance Fee Only?

• Aligned incentives — Kana only earns when users earn
• No cost to enter/exit — encourages participation and reduces friction
• Simple — easy to understand and verify on-chain

Fee Changes

The vault owner can adjust the performance fee, but it cannot exceed 20% (hardcoded maximum in the contract). Fee changes are transparent and visible on-chain.

function setPerformanceFee(uint256 newFee) external onlyOwner {
    require(newFee <= MAX_FEE, "Fee exceeds maximum");
    performanceFee = newFee;
}