Good evening,
Ethereum developers are close to squashing the final few critical bugs on Fusaka Devnet-3 and relaunching non-finality tests on the devnet.
Although the next immediate milestone appears close to completion, several more milestones remain before Fusaka can be considered mainnet-ready.
In today’s newsletter, I explain what those remaining milestones are in Fusaka development.
I also share my views on the newly announced Tempo payments blockchain, which doesn’t differ much from my views on Kraken’s expansion of their tokenized equities services to Ethereum, but I thought it was worth resharing these in the context of a different news item.
Without further ado, below is my full call summary of All Core Developers Testing call #52, along with my key takeaways on the state of Ethereum protocol development.
Yours truly,
Christine D. Kim
Fusaka Devnets
After six days of non-finality, Fusaka Devnet-3 has stabilized. 82% of validators on the network are now correctly attesting to the chain.
Ethereum Foundation (EF) EthPandaOps engineer Barnabas Busa said his team is waiting on fixes from the Nimbus and Erigon client teams before restarting non-finality tests on Devnet-3.
Erigon developer Andrew Ashikhmin said fixes for their client require more investigation and likely will not be ready in the next 24 hours.
Nimbus developer Agnish Ghosh said his team is resolving a bug in their block validation pipeline. They aim to resolve the issue in the next 24 hours.
Representatives from the Teku and Reth client teams shared that they are also investigating and working on various fixes to their software, but these should not be blockers to testing on Devnet-3 or the launch of Devnet-5.
Representatives from the Grandine, Prysm, Lodestar, Geth, Nethermind, and Besu teams shared similar updates, indicating their clients are ready for Devnet-5, aside from a few low-priority issues under investigation.
As debugging efforts are ongoing on Devnet-3, developers have not set a date for Fusaka Devnet-5 launch. Tentatively, developers said they aim to launch Devnet-5 sometime next week.
Busa said the non-finality event on Devnet-3 will be scheduled sometime this week, and if all goes smoothly, developers can schedule the launch of Devnet-5. Devnet-5 will be a large test network, similar to Devnet-4, with over 1,000 validators.
Fusaka Shadow Forks
As background, shadow forks are clones of existing networks, such as public Ethereum testnets or mainnet, used to create a more realistic testing environment for upgrades.
Busa noted that due to an issue with the block schedule field in the Geth and Erigon clients, these clients are unable to support shadow forks.
“Lightclient,” a developer from the Geth team, is working on a fix so that shadow forks can be scheduled with their client.
Ashikhmin said his team will do the same.
Busa asked all client teams to try and aim for Holesky testnet-ready client releases that include finalized BPO values from Devnet-5 testing by September 22nd.
Gas Limit Testing
Testing is ongoing on the capacity of clients to support another block gas limit increase. Nethermind developer Marcin Sobczak said he is running experiments on both the Hoodi testnet and Ethereum mainnet.
Glamsterdam
The initial testing release for block-level access lists (BALs) is out.
Geth developer Jared Wasinger said there are two issues with the specifications for BALs that will impact the testing release. EF STEEL developer Felipe Selmo said once those issues are addressed, a new release can be created later this week.
EEST v5 Release
“Spencer-tb,” also on the EF STEEL team, highlighted the v5 release of Ethereum execution specification tests (EEST). This release prepares EEST for merging with another repository that contains the specifications for the Ethereum execution layer (EL) client, called Ethereum Execution Layer Specifications (EELs).
All code in the EEST repository will be moved to EELs. The switch will not happen immediately, but sometime in Q4 2025. Spencer-tb encouraged developers to review the release notes of EEST v5 for more details on the breaking changes in this release and EEST’s planned migration later this year.
🌻That’s all for my summary of ACDT #52. Continue reading for pointed takeaways from the call, featuring direct quotes and additional context on key topics. To read the rest of the newsletter, make sure you are signed up for a premium subscription:
🌻New to the ACD calls and want to learn more about Ethereum protocol development? Explore the ACD Toolkit, which is included with a premium subscription. It contains evergreen resources and materials that teach you the fundamentals of tracking the evolution of Ethereum like a pro:
🌻I also offer professional consultations on Ethereum protocol development and governance. If you’d like to book a meeting with me to get tailored insights into the evolution of Ethereum for your business or portfolio, please use my Calendly scheduling page:
Editor’s note: Some quotes featured in this section have been edited slightly for grammar and clarity.
Takeaway #1:
Ethereum developers are close to moving past one hurdle in the path to shipping Fusaka on mainnet, but several more remain.
On All Core Developers Testing (ACDT) call #52, Ethereum Foundation (EF) EthPandaOps Engineer Barnabas Busa shared welcome news about the stability of Devnet-3. He said:
