FeeModel.sol

Pure fee-calculation contract for the Strike CLOB protocol. This contract performs no transfers -- all movement of funds is handled by callers (Vault, BatchAuction, etc.). FeeModel only computes amounts.

Inherits: AccessControl (OpenZeppelin).

Fee Schedule

Parameter	Type	Description	Default
feeBps	uint256	Uniform fee in basis points	20 (0.20%)
clearingBountyBps	uint256	Bonus for clearing keeper (admin-configurable, currently disabled)	0
protocolFeeCollector	address	Address that receives the protocol's fee share	deployer

Constant: MAX_BPS = 10_000 (100%).

No maker/taker distinction — both sides of a trade pay half the fee (50/50 split). The extra wei from integer rounding goes to the protocol (sell side pays ceil).

Calculation Functions

calculateFee

function calculateFee(uint256 amount) public view returns (uint256 fee)

Returns the total fee for a given filled collateral amount.

Formula: fee = amount * feeBps / 10_000

calculateHalfFee

function calculateHalfFee(uint256 amount) public view returns (uint256 fee)

Returns the buy-side half of the fee: floor(calculateFee(amount) / 2).

calculateOtherHalfFee

function calculateOtherHalfFee(uint256 amount) public view returns (uint256 fee)

Returns the sell-side half of the fee: calculateFee(amount) - calculateHalfFee(amount) (i.e. ceil(fee / 2)). The sell-side fee is deducted from the seller's USDT payout at settlement.

Admin Functions

All admin functions require DEFAULT_ADMIN_ROLE.

setFeeBps

function setFeeBps(uint256 _feeBps) external

Update the uniform fee. Reverts if _feeBps > MAX_BPS.

setClearingBounty

function setClearingBounty(uint256 _clearingBountyBps) external

Set the clearing bounty percentage (currently disabled, reserved for future use).

setProtocolFeeCollector

function setProtocolFeeCollector(address _collector) external

Update the protocol fee collector address. Reverts if _collector is the zero address.

Events

Event	Parameters	Description
FeeBpsUpdated	uint256 feeBps	Emitted when fee changes
ClearingBountyUpdated	uint256 clearingBountyBps	Emitted when clearing bounty changes
ProtocolFeeCollectorUpdated	address indexed collector	Emitted when fee collector changes

Example

With default parameters (feeBps=20):

• Filled collateral: 100 USDT

• Total fee: 100 * 20 / 10000 = 0.20 USDT

• Buy-side fee: floor(0.20 / 2) = 0.10 USDT

• Sell-side fee: ceil(0.20 / 2) = 0.10 USDT

• To protocol fee collector: 0.20 USDT (sum of both halves)