[config change] Improve timeboost implementation

cmd/nitro/nitro.go

@@ -693,18 +693,6 @@ func mainImpl() int {
 		}
 	}
 
-	execNodeConfig := execNode.ConfigFetcher()
-	if execNodeConfig.Sequencer.Enable && execNodeConfig.Sequencer.Timeboost.Enable {
-		execNode.Sequencer.StartExpressLane(
-			ctx,
-			execNode.Backend.APIBackend(),
-			execNode.FilterSystem,
-			common.HexToAddress(execNodeConfig.Sequencer.Timeboost.AuctionContractAddress),
-			common.HexToAddress(execNodeConfig.Sequencer.Timeboost.AuctioneerAddress),
-			execNodeConfig.Sequencer.Timeboost.EarlySubmissionGrace,
-		)
-	}
-
 	err = nil
 	select {
 	case err = <-fatalErrChan:

execution/gethexec/contract_adapter.go

@@ -0,0 +1,85 @@
+// Copyright 2024-2025, Offchain Labs, Inc.
+// For license information, see https://github.com/nitro/blob/master/LICENSE
+
+package gethexec
+
+import (
+	"context"
+	"errors"
+	"math"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/accounts/abi/bind"
+	"github.com/ethereum/go-ethereum/arbitrum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/ethereum/go-ethereum/eth/filters"
+	"github.com/ethereum/go-ethereum/rpc"
+)
+
+// contractAdapter is an impl of bind.ContractBackend with necessary methods defined to work with the ExpressLaneAuction contract
+type contractAdapter struct {
+	*filters.FilterAPI
+	bind.ContractTransactor // We leave this member unset as it is not used.
+
+	apiBackend *arbitrum.APIBackend
+}
+
+func (a *contractAdapter) FilterLogs(ctx context.Context, q ethereum.FilterQuery) ([]types.Log, error) {
+	logPointers, err := a.GetLogs(ctx, filters.FilterCriteria(q))
+	if err != nil {
+		return nil, err
+	}
+	logs := make([]types.Log, 0, len(logPointers))
+	for _, log := range logPointers {
+		logs = append(logs, *log)
+	}
+	return logs, nil
+}
+
+func (a *contractAdapter) SubscribeFilterLogs(ctx context.Context, q ethereum.FilterQuery, ch chan<- types.Log) (ethereum.Subscription, error) {
+	return nil, errors.New("contractAdapter doesn't implement SubscribeFilterLogs - shouldn't be needed")
+}
+
+func (a *contractAdapter) CodeAt(ctx context.Context, contract common.Address, blockNumber *big.Int) ([]byte, error) {
+	return nil, errors.New("contractAdapter doesn't implement CodeAt - shouldn't be needed")
+}
+
+func (a *contractAdapter) CallContract(ctx context.Context, call ethereum.CallMsg, blockNumber *big.Int) ([]byte, error) {
+	var num rpc.BlockNumber = rpc.LatestBlockNumber
+	if blockNumber != nil {
+		num = rpc.BlockNumber(blockNumber.Int64())
+	}
+
+	state, header, err := a.apiBackend.StateAndHeaderByNumber(ctx, num)
+	if err != nil {
+		return nil, err
+	}
+
+	msg := &core.Message{
+		From:              call.From,
+		To:                call.To,
+		Value:             big.NewInt(0),
+		GasLimit:          math.MaxUint64,
+		GasPrice:          big.NewInt(0),
+		GasFeeCap:         big.NewInt(0),
+		GasTipCap:         big.NewInt(0),
+		Data:              call.Data,
+		AccessList:        call.AccessList,
+		SkipAccountChecks: true,
+		TxRunMode:         core.MessageEthcallMode, // Indicate this is an eth_call
+		SkipL1Charging:    true,                    // Skip L1 data fees
+	}
+
+	evm := a.apiBackend.GetEVM(ctx, msg, state, header, &vm.Config{NoBaseFee: true}, nil)
+	gp := new(core.GasPool).AddGas(math.MaxUint64)
+	result, err := core.ApplyMessage(evm, msg, gp)
+	if err != nil {
+		return nil, err
+	}
+
+	return result.ReturnData, nil
+}