function _validateOrder(bytes memory order) private view {
    (
        address makerToken,
        address takerToken,
        address feeRecipient,
        uint256 makerAmount,
        uint256 takerAmount
    ) = _extractOrderInfo(order);

    // No fee recipient allowed
    require(feeRecipient == address(0), "no fee recipient allowed");

    // MakerToken should never be WETH
    require(makerToken != address(WETH), "maker token must not be WETH");

    // TakerToken (proceeds) should always be WETH
    require(takerToken == address(WETH), "taker token must be WETH");

    address priceOracle = priceOracles[makerToken];

    // Price oracle not defined
    require(priceOracle != address(0), "price oracle not defined");

    uint256 slippageLimit = slippageLimits[makerToken];

    // Slippage limit not defined
    require(slippageLimit != 0, "slippage limit not defined");

    uint256 oraclePrice = _toUint(
        AggregatorV2V3Interface(priceOracle).latestAnswer()
    );

    uint256 priceFloor = (oraclePrice * slippageLimit) /
        SLIPPAGE_LIMIT_PRECISION;

    uint256 makerDecimals = 10**ERC20(makerToken).decimals();

    // makerPrice = takerAmount / makerAmount
    uint256 makerPrice = (takerAmount * makerDecimals) / makerAmount;

    require(makerPrice >= priceFloor, "slippage is too high");
}
