Using flashbots as a backdoor path to account abstraction about pm

[adietrichs]

Ah, really interesting!
Most of our work on EIP-2938 was on creating the mempool rules for identifying "safe" transactions. I think those could potentially be adapted to this new use case. In addition to these safe rules, flashbot relayers could also offer to accept packages with more complex payment behaviour, similar to the general MEV case.

[amanusk]

Some thoughts on this since I had a very similar idea.
Basically described here: https://twitter.com/amanusk_/status/1370642493621080071

The interesting part for me was that by using flashbots, no extra contracts were needed.
This means that anyone can be the relayer, including the EOA itself that had no ETH.

This solution has downsides. In this simple scenario, the bundle had to be executed to its completion, otherwise, the account would not have enough ETH to cover the costs of the transaction.
If a third-party relayer (with ETH) would have sent the bundle on behalf of the EOA, the miner could theoretically only mine the Tx that pays them, without doing all the actual work. This must be taken into consideration, even if currently miners execute bundles as-is.
(Edit: it is also true that Txs in this case could only execute in-order because of the nonce, but it is still true that this would not have been the case if a third party executed these on the EOA's behalf)

Wrapping and executing the bundle in a smart contract wallet, and only paying the block.coinbase would solve this, but solutions similar to that already exist (e.g. any.sender -> ITX)

Another limitation here that is currently in place is that there is currently only one bundle in each block. "Regular" txs would find it hard to compete with other bots that use the bundles to extract MEV (e.g. by sandwiching DEX trades).
This can make more sense once multiple independent bundle can be included in each block. Correct and fair ordering of bundles in a block is an interesting problem to solve.

[PhiMarHal]

the idea that _ every transaction needing to start from an "externally-owned account" (EOA) controlled by a private key,

This might be missing "instead of" or "rather than".

[vbuterin]

Thanks! Fixed.

[zhous]

Wow, so everyone owns a machine gun! That's an incredible excited spectacle!

[Multimyst]

Wow,This is a brand new attempt！

[ErikBjare]

How is this affected by EIP-1559? Specifically what @koeppelmann mentioned here: https://twitter.com/koeppelmann/status/1381922898617757696

[livingrock7]

If a third-party relayer (with ETH) would have sent the bundle on behalf of the EOA, the miner could theoretically only mine the Tx that pays them, without doing all the actual work. This must be taken into consideration, even if currently miners execute bundles as-is.

@amanusk can you elaborate more on this
Also, could you pay to particular pool address instead of block.coinbase and relay bundles to them?

[sidutta]

If a third-party relayer (with ETH) would have sent the bundle on behalf of the EOA, the miner could theoretically only mine the Tx that pays them, without doing all the actual work. This must be taken into consideration, even if currently miners execute bundles as-is.

@amanusk can you elaborate more on this
Also, could you pay to particular pool address instead of block.coinbase and relay bundles to them?

A bundle is a set of txns. If the miner bribe comes from a 3rd party relayer with its txn nonce not being dependent on the rest, a miner can only execute the bribe txn while dropping the rest of the txns in the bundle.