Isthmus upgrade: Hardfork Planning

[BlocksOnAChain]

• We will use this discussion to do a public "brainstorm" about the potential scope and ideas that we want to include for the isthmus hardfork that follows Holocene. This fork is targeting Governance Cycle 33, which starts of February 6th.
• Feel free to share your ideas and specifications with the community, so we have a great public planning session for our upcoming network upgrade

[yuwen01]

I propose adding another transaction fee, called the OperatorFee. This fee allows new OP chain variants to account for their unique cost structure. For example, the existing fee structure isn't friendly to chains using alt-DA's, since the l1fee only accounts for Ethereum's blobGasFee instead of an alt-DA's fee.

Design Doc
Spec

REVM implementation WIP
OP-Geth implementation WIP
Optimism monorepo implementation WIP
OP-alloy implementation WIP

[tynes]

Definitely in favor of including this

[BlocksOnAChain]

I support this suggestion and I think we should include it for Isthmus hardfork.

[tynes]

I propose that we include the "Standard L2 Genesis" project, the design doc can be found here

[mds1]

I propose that we include an upgrade of all L1 and L2 Solidity contracts to 0.8.25, as agreed upon in ethereum-optimism/design-docs#106

[tynes]

I propose that we include the Pectra changes into the OP Stack as part of Isthmus. Getting EIP-7702 early is important for bleeding edge applications to deploy to OP Stack chains.

See https://eips.ethereum.org/EIPS/eip-7600 for scope

• Span batch changes are required for 7702, see Pectra: Span Batch Support #318
• We should make sure that the BLS precompiles aren't too expensive in the fault proof

From @ajsutton

For whenever we pull Pectra into the OP stack, we will need to do some benchmarking on the new BLS precompiles - there's a pretty high likelihood we'll need to apply the preimage oracle acceleration to them. Since the G1/G2 MSM precompile pairing check operation has a variable gas cost if it needs to go via the preimage oracle we will need to include a maximum input length for the precompile to ensure any call to it on L2 can be executed on L1 with some gas to spare to store the result in the preimage oracle.

[vdamle]

I propose that we include the L2 withdrawals root in block header feature in Isthmus (it was de-scoped from Holocene)

ref: ethereum-optimism/optimism#12044

WIP:

#396
ethereum-optimism/op-geth#383
ethereum-optimism/op-geth#399

[mds1]

I propose that we include the Custom Gas Token (CGT) code.

The standard config does not change, and still requires ETH as the gas token to be a standard chain. Therefore, functionally, there is no change by including this feature. The rationale is that CGT code is currently coupled with other code, and it's less work to just ship the CGT as a regular feature (and have it part of OPCM, etc) and require that standard chains don't use this feature, than to decouple the code

[maurelian]

I propose that we add changes to the L1 contracts required to enable L1 upgrades via the OPCM.