Optimistic Relaying Process

Simple guide for Builders wanting to use Optimistic Relaying

h/t to our friends at ultrasound relay for devising the Optimistic Relaying process.

Notes

• Promoting a builder pubkey to Optimistic is a manual process - please reach out to us to have this enabled.

• Optimistic relaying will only happen if your builder pubkeys are promoted by us and the associated collateral is greater than the bid value.

• Following a demotion, Optimistic relaying will be manually re-enabled only once the underlying root cause has been identified and addressed.

• Please reach out to us to link multiple pubkeys to the same Builder ID

Collateral

• Collateral must be posted to titanrelay.eth from your primary builder fee recipient address.

• Maximum collateral per pubkey is currently 64 ETH for optimistic v1 and 32 ETH for optimistic v2 (subject to change).

• If you would like to have your collateral returned and stop optimistic relaying please reach out to us.

Incidents

• If a proposer is the victim of an incident related to a bad bid they must be made whole by the Builder of the full bid value.

• Builders are expected to send ETH directly to the proposers fee recipient address to make them whole within 24 hours of the incident occurring.

• If proposers aren't made whole within 24 hours we may use the Builders' collateral to compensate the proposer directly.

• We reserve the right to publish a public post-mortem of any incidents relating to bad bids.

Filtering

• While we are strongly committed to network neutrality and censorship resistance, we are also realists and understand that some proposers, particularly in the US, may face regulatory and/or reputational risks based on dynamic and/or grey area interpretations. So we provide proposers with a choice. By default their blocks are not filtered but if they opt in to filtering then they will be.

• There are 2 aspects to filtering:

  • The builder is informed via the BuilderGetValidatorsResponse that they must filter out transactions that touch a blacklisted address. This list is currently based upon the OFAC List.

  • Blocks are screened by the relay to ensure the builder has adhered the blacklist policy.

• There are 3 ways the screening on the relay side can be handled when the builder has opted in to optimistic relaying:

  • The default approach: This disables optimistic relaying for these slots to ensure that all blocks have been fully screened before being accepted by the auctioneer.

  • The optimistic filtering approach: Builders may opt into optimistic filtering if they meet the following criteria:

    • At least 180 days of optimistic submissions

    • No demotions for submitting blocks containing blacklisted transactions in the past 90 days

    In this mode, blocks are provisionally accepted prior to full screening. If a block fails screening, the builder is immediately suspended from optimistic filtering until the issue is resolved.

  • The bespoke approach: Proposers who are uncomfortable with the optimistic filtering approach can opt out by disabling optimistic relaying for their slots. In the future, they may also have the option to select trusted builders for optimistic submissions.

List of builders approved for optimistic filtering:

• Titan

• BuilderNet

• BobTheBuilder

If your builder meets the criteria and you would like to be add contact us