Configuration

The OP Stack is a flexible platform with various configuration values that you can tweak to fit your specific needs. If you’re looking to fine-tune your deployment, look no further.

🚧 Work in Progress

OP Stack configuration is an active work in progress and will likely evolve significantly as time goes on. If something isn’t working with your configuration, check back with this page to see if anything has changed.

New Blockchain Configuration

New OP Stack blockchains are currently configured with a JSON file inside the Optimism repository. The file is <optimism repository>/packages/contracts-bedrock/deploy-config/<chain name>.json. For example, this is the configuration file for the tutorial blockchain (opens new window).

Admin accounts

Key	Type	Description	Default / Recommended value
finalSystemOwner	L1 Address	Address that will own all ownable contracts on L1 once the deployment is finished, including the ProxyAdmin contract.	It is recommended to have a single admin account to retain a common security model.
controller	L1 Address	Address that will own the SystemDictator contract and can therefore control the flow of the deployment or upgrade.	It is recommended to have a single admin account to retain a common security model.
proxyAdminOwner	L2 Address	Address that will own the ProxyAdmin contract on L2. The L2 ProxyAdmin contract owns all of the Proxy contracts for every predeployed contract in the range 0x42...0000 to 0x42..2048. This makes predeployed contracts easily upgradeable.	It is recommended to have a single admin account to retain a common security model.

Fee recipients

Key	Type	Description	Default value
baseFeeVaultRecipient	L1 or L2 Address	Address that the base fees from all transactions on the L2 can be withdrawn to.	It is recommended to have a single admin account to retain a common security model.
l1FeeVaultRecipient	L1 or L2 Address	Address that the L1 data fees from all transactions on the L2 can be withdrawn to.	It is recommended to have a single admin account to retain a common security model.
sequencerFeeVaultRecipient	L1 or L2 Address	Address that the tip fees from all transactions on the L2 can be withdrawn to.	It is recommended to have a single admin account to retain a common security model.

Minimum Fee Withdrawal Amounts

Key	Type	Description	Default value
baseFeeVaultMinimumWithdrawalAmount	Number in wei	The minimum amount of funds the BaseFeeVault contract must have for a fee withdrawal.	10 ether
l1FeeVaultMinimumWithdrawalAmount	Number in wei	The minimum amount of funds the L1FeeVault contract must have for a fee withdrawal.	10 ether
sequencerFeeVaultWithdrawalAmount	Number in wei	The minimum amount of funds the SequencerFeeVault contract must have for a fee withdrawal.	10 ether

Withdrawal Network

Key	Type	Description	Default value
baseFeeVaultWithdrawalNetwork	Number representing network enum	A value of 0 will withdraw funds to the recipient address on L1 and a value of 1 will withdraw funds to the recipient address on L2.
l1FeeVaultWithdrawalNetwork	Number representing network enum	A value of 0 will withdraw funds to the recipient address on L1 and a value of 1 will withdraw funds to the recipient address on L2.
sequencerFeeVaultWithdrawalNetwork	Number representing network enum	A value of 0 will withdraw funds to the recipient address on L1 and a value of 1 will withdraw funds to the recipient address on L2.

Misc.

Key	Type	Description	Default value
numDeployConfirmations	Number of blocks	Number of confirmations to wait when deploying smart contracts to L1.	1
l1StartingBlockTag	Block hash	Block tag for the L1 block where the L2 chain will begin syncing from. Generally recommended to use a finalized block to avoid issues with reorgs.
l1ChainID	Number	Chain ID of the L1 chain.	1 for L1 Ethereum mainnet, 5 for the Goerli test network. See here for other blockchains (opens new window).
l2ChainID	Number	Chain ID of the L2 chain.	42069

Blocks

These fields apply to L2 blocks: Their timing, when do they need to be written to L1, and how they get written.

Key	Type	Description	Default value
l2BlockTime	Number of seconds	Number of seconds between each L2 block. Must be <= L1 block time (12 on mainnet and Goerli)	2
maxSequencerDrift	Number of seconds	How far the L2 timestamp can differ from the actual L1 timestamp	600 (10 minutes)
sequencerWindowSize	Number of blocks	Maximum number of L1 blocks that a Sequencer can wait to incorporate the information in a specific L1 block. For example, if the window is 10 then the information in L1 block n must be incorporated by L1 block n+10.	3600 (12 hours)
channelTimeout	Number of blocks	Maximum number of L1 blocks that a transaction channel frame can be considered valid. A transaction channel frame is a chunk of a compressed batch of transactions. After the timeout, the frame is dropped.	300 (1 hour)
p2pSequencerAddress	L1 Address	Address of the key that the Sequencer uses to sign blocks on the p2p network.	Sequencer, an address for which you own the private key
batchInboxAddress	L1 Address	Address that Sequencer transaction batches are sent to on L1.	0xff00…0042069
batchSenderAddress	L1 Address	Address of the account that nodes will filter for when searching for Sequencer transaction batches being sent to the batchInboxAddress. Can be updated later via the SystemConfig contract on L1.	Batcher, an address for which you own the private key

Proposal fields

These fields apply to output root proposals.

Key	Type	Description	Default value
l2OutputOracleStartingBlockNumber	Number	Block number of the first OP Stack block. Typically this should be zero, but this may be non-zero for networks that have been upgraded from a legacy system (like Optimism Mainnet). Will be removed with the addition of permissionless proposals.	0
l2OutputOracleStartingTimestamp	Number	Timestamp of the first OP Stack block. This MUST be the timestamp corresponding to the block defined by the l1StartingBlockTag. Will be removed with the addition of permissionless proposals.
l2OutputOracleSubmissionInterval	Number of blocks	Number of blocks between proposals to the L2OutputOracle. Will be removed with the addition of permissionless proposals.	120 (24 minutes)
finalizationPeriodSeconds	Number of seconds	Number of seconds that a proposal must be available to challenge before it is considered finalized by the OptimismPortal contract.	We recommend 12 on test networks, seven days on production ones
l2OutputOracleProposer	L1 Address	Address that is allowed to submit output proposals to the L2OutputOracle contract. Will be removed when we have permissionless proposals.
l2OutputOracleChallenger	L1 Address	Address that is allowed to challenge output proposals submitted to the L2OutputOracle. Will be removed when we have permissionless challenges.	It is recommended to have a single admin account to retain a common security model.

L1 data fee

These fields apply to the cost of the L1 data fee (opens new window) for L2 transactions.

Key	Type	Description	Default value
gasPriceOracleOverhead	Number	Fixed L1 gas overhead per transaction. Default value will likely be adjusted with more information from the Optimism Goerli deployment.	2100
gasPriceOracleScalar	Number	Dynamic L1 gas overhead per transaction, given in 6 decimals. Default value of 1000000 implies a dynamic gas overhead of exactly 1x (no overhead).	1000000

EIP 1559 gas algorithm

These fields apply to the EIP 1559 algorithm (opens new window) used for the L2 execution costs (opens new window) of transactions on the blockchain.

Key	Type	Description	Default value	Value on L1 Ethereum
eip1559Denominator	Number	Denominator used for the EIP1559 gas pricing mechanism on L2 (opens new window). A larger denominator decreases the amount by which the base fee can change in a single block.	50	8
eip1559Elasticity	Number	Elasticity for the EIP1559 gas pricing mechanism on L2 (opens new window). A larger elasticity increases the maximum allowable gas limit per block.	10	2
l2GenesisBlockGasLimit	String	Initial block gas limit, represented as a hex string. Default is 25m, implying a 2.5m target when combined with a 10x elasticity.	0x17D7840
l2GenesisBlockBaseFeePerGas	String	Initial base fee, used to avoid an unstable EIP1559 calculation out of the gate. Initial value is 1 gwei.	0x3b9aca00

Governance token

The governance token is a side-effect of use of the OP Stack in the Optimism Mainnet network. It may not be included by default in future releases.

Key	Type	Description	Default value
governanceTokenOwner	L2 Address	Address that will own the token contract deployed by default to every OP Stack based chain.
governanceTokenSymbol	String	Symbol for the token deployed by default to each OP Stack chain.	OP
governanceTokenName	String	Name for the token deployed by default to each OP Stack chain.	Optimism