Ethereum Glamsterdam Upgrade Could Break the Chain, Developers Warn

Several prominent developers are urging core developers to halt the Ethereum Glamsterdam upgrade in its current form. They warn that its planned gas changes could break smart contracts that hold user funds.

“Please don’t break the chain,” wrote the founder of Curve Finance. “It looks like the Glamsterdam upgrade would lead to another emergency hard fork back, with a lot of drama.”

Developers Push Back on Ethereum Glamsterdam Gas Plan

At the center of the dispute is EIP-8037, which raises gas costs for creating new state, such as storage entries and new contracts.

However, some smart contracts set a fixed gas amount for these steps or check the remaining gas during a transaction.

Once prices rise, those calls could run out of gas and fail. Because deployed contracts are immutable, developers cannot simply patch them, which could leave user funds stuck.

A prominent DeFi developer called the plan “completely ridiculous.”

this is completely ridiculousbesides the already huge list of 200,000 affected contracts in ethereum/repricing-impact, i found multiple methodological issues that make it miss many more.it affects deployment and operation of several high profile protocols, not just some… https://t.co/g4CnI20fKz

— banteg (@banteg) November 7, 2026

Another developer said his team had found the same issues a security firm later flagged, even before Glamsterdam went live on the Sepolia testnet.

“Rushing out Glamsterdam now disregarding the community feedback would be a mistake,” the developer wrote.

An Ethereum Foundation board member also opposed the upgrade. “I’m not gonna push for a fork that breaks invariants that were unknown until ~2 weeks ago,” the security researcher wrote.

The criticism follows earlier trouble for Ethereum Glamsterdam, one of two major upgrades developers planned for 2026. In October, core developers delayed a Glamsterdam test on the Hoodi testnet after security researchers flagged risks.

Ethereum Advocate Reverses Call for Fast Activation

The pushback even changed minds among Ethereum Glamsterdam supporters. An influential Ethereum community member first called for activation “asap.” In his view, Ethereum guarantees access to the network, not specific gas prices.

Hours later, however, the advocate reversed course. “We should (clearly, now) not continue towards Glam activation asap. I was wrong to say so,” he wrote. The problem, he added, is “essentially worse than is generally understood.”

The advocate also admitted that the community collectively failed on the design, due diligence, and public communication. Gas introspection, he wrote, is “a very serious issue that needs immediate remediation and way more sunlight.”

The bad news on Glam's gas opcode repricing debacle is that we collectively fucked up the design, adequate diligence, and sufficient public communication for us to sooner come to correct consensus on the issue.The good news imo is that we have learned a lot over the years about…

— Ryan Berckmans ⟠ (@ryanberckmans) November 7, 2026

As a result, core developers face pressure to publish more data before Ethereum Glamsterdam reaches mainnet. The dispute also lands as Ethereum ETFs log their worst month for flows since launch.

Meanwhile, Ethereum co-founder Vitalik Buterin has already called the next upgrade, Hegota, Ethereum’s last “normal” fork.