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Megabundles support added

Relays can merge bundles and suggest them for profit switching. Miners can define a list of trusted relay addresses from which megabundles are accepted.

Scoring function does not change between v0.3 and v0.4:

sv0.34=Δcoinbase+TUgTmTTMUgTmTTUgTs_{v0.3-4} = \frac{\Delta_{coinbase} + \sum_{T\in U}g_Tm_T - \sum_{T\in M \cap U}g_Tm_T}{\sum_{T\in U}g_T}

ss: bundle UU score used to sort bundles.
UU: ordered list of transactions TT in a bundle.
MM: set of transactions TT in the mempool.
gTg_{T}: gas used by transaction TT.
pTp_{T}: gas price of transaction TT.
cTc_{T}: fee cap per gas of transaction TT.
δT\delta_T: priority fee per gas of transaction TT.
eTe_{T}: effective fee per gas of transaction TT equal min\min(cTc_{T}, BASEFEE + δT\delta_T).
mTm_{T}: miner fee per gas of transaction TT equal eTe_{T} - BASEFEE.
Δcoinbase\Delta_{coinbase}: coinbase difference from direct payment.


September, 10th 2021

Final spec of version alpha-v0.4 ready

Flashbots reference implementation ready

Flashbots Goerli running on version alpha-v0.4

Start of miners custom implementations and testing

September, 22nd 2021

End of miners custom implementation and testing

September, 27th 2021

All miners running on v0.4

Flashbots mainnet relay switching to alpha-v0.4

Upgrade Steps

  • Miners asked to upgrade to v1.10.8-mev0.4.0
  • Miners can update 100% of capacity to this new version
  • Miners will need to upgrade to the newest version of mev-proxy or whitelist the RPC call eth_sendMegabundle for your specific environment.
  • Miners must add a new command line parameter for Megabundle Relays (see below)

Node configuration

Miners must configure a new command line parameter to specify which relays megabundles will be accepted. The parameter is set as follows for a list of 3 relayers.


The default Mega Bundle Relayer is set to the Flashbots Relayer 0x870e2734DdBe2Fba9864f33f3420d59Bc641f2be. If you only want to receive bundles from this default relayer no configuration is necessary. For configurations which allow more relayers, be sure to also include the Flashbots relayer in your configuration.