interface IFeraReferral {
    /**
     * @dev Record referral.
     */
    function recordReferral(address user, address referrer) external;

    /**
     * @dev Record referral commission.
     */
    function recordReferralCommission(address referrer, uint256 commission) external;

    /**
     * @dev Get the referrer address that referred the user.
     */
    function getReferrer(address user) external view returns (address);
}
function getReferrer(address user) external view returns (address);

/**
 * @dev Get the referrer address that referred the user.
 */