Note: If the refundPercent field is set, the builder will construct a refund transaction automatically. However, if the refund amount does not cover the cost of the transaction (i.e., gas_used * base_fee), the bundle will be discarded.
Consider the following Bundle:
TXN 1 - User swap (Base fee: 50 Gwei, Piority fee 3 Gwei, Gas: 280k)
TXN 2 - Backrun (Base fee: 50 Gwei, Priority fee 100 Gwei, Gas: 150k)
Current block base fee: 50 Gwei
ETH reward of the last transaction in the bundle = (150k x 100 Gwei) = 15000 Gwei
ETH reward after transfer transaction fees = 15000 - (21k x 50 Gwei) = 13950 Gwei
Refund amount = 0.9 x 13950 Gwei = 12555 Gwei
Our builder supports Sponsored Bundles. If we receive a bundle that fails with LackOfFundForGasLimit error, we will automatically send the ETH required to cover the gas fees and value transfer for the transaction to succeed.
The caveat here is that the bundle must of course increase the builder balance, as we will need to recoup this sponsoring cost with the bundle’s execution.
For further details, see our substack article.
Note: the replacementUuid must have been set when the bundle was submitted.
N.B.: We cannot guarantee that the bundle will be canceled if the cancellation is submitted within 4 seconds of the final relay submission.
eth_sendRawTransaction / eth_sendPrivateRawTransaction
Authentication via Flashbots standard is optional but encouraged. By default, authentication moves you into the Medium Priority queue.
There are three priority queues:
Higher priority queues have higher inclusion rates as bundles will be added to the pool faster, allowing for later submissions.
Our builder will submit only using the following public keys:
Any public key not included in the above list should be considered unrelated to our builder.
Our builder runs multiple sorting algorithms concurrently that compete against each other to produce the most valuable block possible.
Sorting of bundles and transactions is not necessarily ranked by effective gas price, and as such top-of-block execution is not guaranteed. Based on how transactions interact with each other and the current state, including transactions with lower effective gas prices before higher paying ones may yield more valuable blocks, which is what our algorithms optimise for.
We will never unbundle a bundle, and will never broadcast any bundles or private transactions to the public mempool.
View searcher priority status with eth_getUserStatsV2.