        if (params.coinbase == address(0)) {
        params.coinbase = msg.sender;
    }
                // When a hook is called, all ether in this contract will be send to the hook.
            // If the ether sent to the hook is not used entirely, the hook shall send the Ether
            // back to this contract for the next hook to use.
            // Proposers shall choose use extra hooks wisely.
            IHook(params.hookCalls[i].hook).onBlockProposed{ value: address(this).balance }(
                blk, meta_, params.hookCalls[i].data
            );
        // The proposer irrevocably pays a fee to the assigned prover, either in
    // Ether or ERC20 tokens.
    if (assignment.feeToken == address(0)) {
        // Paying Ether
        _blk.assignedProver.sendEther(proverFee, MAX_GAS_PAYING_PROVER);
    } else {
        // Paying ERC20 tokens
        IERC20(assignment.feeToken).safeTransferFrom(
            _meta.coinbase, _blk.assignedProver, proverFee
        );
    }
    if (params.coinbase == address(0 || params.coinbase != msg.sender)) {
        params.coinbase = msg.sender;
    }
