Optimism Rollup FAQ

1. What Optimism versions do you support? We regularly update our version support as new releases come in. At the moment, we deploy OP chains using v1.7.0.

2. What data availability options do you support? We support EigenDA, Celestia, Avail, and AWS S3, at the moment using v1.7.0.

3. What is included in the standard setup?

Parameter	Value
OP chain	1 sequencer node (geth / node / batcher / proposer)
RPC / WS data	1 or more load-balanced full nodes
Block explorer	Standard Blockscout v2 application
Bridge	Chain registration in our bridge application

4. What is the rollup setup process like?

   In brief, the steps are:

   1. Deployment of rollup contracts (Bedrock) on the parent chain

   2. Deployment of the nodes for your chain

   3. Registration in the bridge application

5. Is custom gas token supported? No, only the native token on the parent chain is currently supported.

6. Who receives the fees on the OP chain? Fees are covered in this document: https://docs.optimism.io/builders/dapp-developers/transactions/fees

   There are three configurable recipients for:

   • Base fees

   • L1 fees

   • Sequencing fees (from “priority fee”)

   Fee recipient addresses must be configured during chain genesis and cannot be changed thereafter.

7. What parameters can we configure for our OP chain?

   You can provide us with your preferred:

   • Chain ID (if no preference, we’ll generate a random ID)

   • Network name

   • Block time (if no preference, we’ll default to 10s)

8. Can I quickly try out an OP rollup somewhere? We provide a public testnet that you can use to test out the Optimism rollup: https://rollup-info.altlayer.io/public/op_testnet

9. Can we host our own full nodes? Yes, and in fact hosting your own full nodes is recommended if you have query-intensive applications for your chain, such as an indexer. Upon request, we will provide you with the scripts for launching your own full nodes.

10. Can we use our own domain for the chain URLs? Yes, you can CNAME the RPC, websocket (if any) and explorer URLs to your own domain.

    For these customizations, you will need to create CNAME records on your DNS provider. We will provide you the target for these records.

11. Can we customize our block explorer UI? Yes, we can customize settings such as the logos, icons, color scheme, and text content. Please request our Blockscout order form to see all the customizations available.

12. Can I verify contracts on the block explorer? Yes. Please follow this sample for verifying a deployed contract using hardhat or foundry.

13. How are gas fees calculated? Please refer to this document for calculating fees: https://docs.optimism.io/builders/dapp-developers/transactions/fees

    Do note that if you use a data availability option, the tx_data will be significantly smaller, resulting in smaller fees for the settlement. This smaller fee, however, does not take into account the fees incurred due to the DA storage for that transaction. That fee will likely be absorbed by you on the DA chain.

14. What are our bridging options? By default, your rollup chain is registered into our bridge application. Should you instead wish to maintain your own bridge, all the necessary contract addresses are provided to you.

15. Can we customize our bridge app UI? We can customize the icon that appears for your network as shown below.

    
16. What can we expect after the chain setup is completed? You will receive a rollup info page containing all the L2 details and links, similar to this.

17. Do you support migrations to alternative DAs or addition of restaked rollup modules after the OP rollup is live? We are currently in the midst of adding this capability.