Ethereum’s ambitious plan to speed up its network upgrades is facing a critical test as its core developers clash over key changes to the blockchain’s technical architecture that could have drastic consequences for an ecosystem worth billions in value.
The disagreements swirl around how to implement the EVM Object Format (EOF), a container format that works by improving how code and data in Ethereum smart contracts are separated.
EOF works by doing safety checks on EVM bytecode upfront, instead of during execution. Bytecodes are low-level instructions that the Ethereum Virtual Machine (EVM) could understand and work with.
The intended effect of EOF is to make applications on the network run faster and cheaper, while also preventing certain types of validation errors that could cause problems along the way.
The rift emerged during the February 13 All Core Developers Execution Call (ACDE), when the Geth team, which maintains Lightclient, Ethereum’s most widely used client software, expressed its opposition to including the EOF for Fusaka, despite it being months ahead in preparation and testing.
“We disagree that EOF should be shipped on mainnet at all,” the Geth team wrote in comments over the Zoom chat, indicating that their perspective leans toward removing EOF from the Fusaka upgrade altogether.
However, this point of view does not represent any collective consensus, with Geth developer Marius van der Wijden saying that the Geth team works “mostly as individuals.”
“I don’t think we should force team members to ‘fall into the party line,'” Van der Wijden stated during the call.
Van der Wijden has been a vocal critic of EOF implementation for Ethereum’s imminent Pectra upgrade.
“The biggest issue I see is that EOF is extremely complex,” Van der Wijden wrote in a blog last year.
Van der Wijden notes that EOF “only makes existing things slightly faster or slightly cheaper,” while “the drawbacks strongly outweigh the potential benefits.”
But half a year later, it seems that Van der Wijden no longer cares.
My official current thoughts on the #EOF debate pic.twitter.com/G2shcE1IOp
— MariusVanDerWijden (@vdWijden) February 13, 2025
Picking up the pace
Tim Beiko, Ethereum Foundation’s Protocol Support Lead, confirmed the more immediate Pectra upgrade will proceed to public testnets Holesky and Sepolia on February 24 and March 5 respectively, with mainnet deployment targeted for April 8.
To address mounting tensions, Beiko proposed an extended timeline for finalizing Fusaka’s scope: a new deadline for proposing new improvement proposals (March 13), another for coming to terms on upgrade preferences (March 27), and a final decision on what Fusaka should include (April 10).
The Geth team’s resistance to EOF also opens broader concerns about how fast Ethereum could turn things around.
“We need to try and figure out what [proposals] fit best with the goals we want to have the next 12 months and then go from there,” a Geth developer said during the call, advocating for a more measured approach to how Ethereum could be improved.
Meanwhile, Reth developer Roman Krasiuk emphasized the importance of maintaining momentum: “We would never get to a faster pace if we don’t commit ahead of time to the scope.”
Independent developers and other client teams continue supporting EOF’s inclusion, with ongoing testing on dedicated development networks alongside other planned improvements for data availability on the network.
Van der Wijden, Beiko, and a researcher for the Ethereum Foundation did not immediately return requests for comment from Decrypt.
