Ethereum Glamsterdam Hoodi upgrade postponed over EIP-8037

Key takeaways

• Ethereum core developers have postponed the Glamsterdam upgrade on the Hoodi testnet. It had been due on October 26, 2026 at 17:42:48 UTC (epoch 132,352). No new date has been set.
• According to the Ethereum Foundation, the delay allows "further investigation of interactions of EIP-8037 with mainnet smart contracts." EIP-8037 reprices the gas cost of creating new state.
• Security firm ChainSecurity found that the new gas rules could change how some deployed contracts handle failed calls. CoinDesk and crypto.news reported its findings, and crypto.news said the firm cited 13 real-world examples of contracts that could be affected.
• Hoodi node operators must update both their execution and consensus clients before October 26 so that their nodes do not try to activate the cancelled fork.
• No Glamsterdam mainnet date has been confirmed. Developers had discussed December 1, 8 and 9 as possible dates.

Why the Ethereum Glamsterdam upgrade on Hoodi was postponed

The Ethereum Glamsterdam Hoodi upgrade has been postponed. The Ethereum Foundation announced on October 22 that core developers called off the October 26 activation to investigate how EIP-8037 interacts with mainnet smart contracts. No new date has been set.

The Foundation's stated reason is narrow. Developers want more time to study how EIP-8037, one of Glamsterdam's gas-repricing proposals, would interact with smart contracts already deployed on mainnet. The post says plainly: "A new activation date has not been set."

Hoodi is the testnet that validators and staking providers use to rehearse an upgrade before it reaches mainnet. Under Ethereum's usual process, a fork is tested on public testnets before developers set a mainnet date. A Hoodi delay therefore pushes back the point at which a mainnet date can be chosen. Glamsterdam already went live on the Sepolia testnet on October 6, according to CoinDesk, and the Hoodi decision does not reverse that.

What exactly was postponed

According to the Foundation, the revised Hoodi configuration removes three changes that were set for the same epoch:

• the Amsterdam activation on the execution layer;
• the Gloas activation on the consensus layer (Glamsterdam is the combined name for the two);
• a rise in Hoodi's gas limit to 200 million.

The Foundation says the change only rolls back the configuration for the future upgrade and does not revert any of Hoodi's chain history.

Timeline

What EIP-8037 changes

EIP-8037, titled "State Creation Gas Cost Increase," is in Last Call status, with a review deadline of November 1, 2026. It targets state growth: the permanent data, such as accounts, storage slots and contract code, that every full node must keep. The authors cite a Geth state database of about 390 GiB in January 2026. They estimate state would grow by about 387 GiB a year at a 200 million gas limit if pricing stayed the same.

To slow that growth, the proposal sets a single price per byte of new state, called CPSB, at 1,530 gas. It also splits gas into two dimensions: regular execution gas and "state gas." State charges are drawn first from a separate per-transaction state gas reservoir and then from ordinary remaining gas. When a state-creating operation is reverted, the state gas it used is refunded.

The design has been debated before. Anders Elowsson, one of the EIP's authors, has written on Ethereum Research about economic "failure modes" of the state-gas model. These are cases where state creation and regular execution are out of balance. That debate is about how fees behave across the network, not about the contract-safety issue behind this delay.

Source: EIP-8037 specification, eips.ethereum.org, as retrieved on October 23, 2026. Values may still change before the EIP is final.

A companion proposal, EIP-8038, changes the cost of accessing existing state. Crypto.news reports that ChainSecurity's concerns came from the two proposals working together.

What ChainSecurity found

Many contracts call other contracts and then check how much gas is left to decide what to do next. This is common in batched transactions, withdrawal queues and relayer systems. A contract may treat a failed call as final and record it, or treat it as temporary and let the user try again. Some contracts also pass a fixed amount of gas to the contract they call. These patterns were built for today's gas schedule.

CoinDesk and crypto.news describe the risks that ChainSecurity's October 13 assessment found under the proposed rules:

• Too much gas left after a failure. State gas used inside a failed sub-call can be refunded when the changes are undone. The calling contract may then have more gas than its authors expected. A step that would have reverted the whole transaction before could now finish. Crypto.news says this could let some applications mark an operation as failed while preventing the user from retrying it.
• Too little gas for a valid action. CoinDesk reports that creating a new storage slot could require 110,020 gas once the separate state allowance runs out, compared with 22,100 under the current rules. A contract that sends a fixed amount of gas could then fail during an otherwise valid operation.

Crypto.news says ChainSecurity reported 13 real-world examples of contracts that could be affected. The projects have not been named publicly while responsible disclosure is under way. CoinDesk notes that ChainSecurity demonstrated the mechanisms but has not shown that any major production protocol is exploitable. It also notes that the findings do not suggest existing contracts are being exploited now, because the new rules are not live on mainnet.

The Ethereum Foundation's post does not mention ChainSecurity by name. It refers only to the need to investigate EIP-8037's interactions with mainnet contracts. It is not yet known whether developers will change the EIP, add mitigations, or ask affected projects to update their contracts.

What Hoodi node operators need to do

For anyone running Hoodi infrastructure, the postponement is not a "do nothing" event. A node still configured for the old activation would try to fork at epoch 132,352 while the rest of the network does not. The Foundation's guidance is:

1. Check both your execution-layer and consensus-layer clients for instructions that reflect the postponement. Do this before October 26.
2. Do not rely on the client release table in the earlier Glamsterdam announcement. Use a release whose notes explicitly confirm that the October 26 activation has been removed.
3. Validators must update both the beacon node and the validator client.
4. Update any custom configuration that still schedules the old activation.
5. Operators using external block-building infrastructure should follow their provider's instructions.

Source: Ethereum Foundation blog, Glamsterdam on Hoodi postponement post, as retrieved on October 23, 2026. The Foundation said it will link further releases as client teams confirm them.

Researcher Christine D. Kim also warned operators on X, according to crypto.news. She advised them to go back to older releases without the scheduled upgrade, or to wait for a client release that removes it. The Foundation said mainnet users and ETH holders do not need to take any action.

What it means for the December mainnet dates

Before the delay, developers had discussed December 1, 8 and 9 as possible mainnet activation dates, crypto.news reports. None was confirmed. The Foundation's post does not set a mainnet date and gives no timeline for the new Hoodi schedule.

Developers usually want a smooth testnet run, followed by a gap, before they commit to a mainnet date. A Hoodi slot has not been rescheduled, so any December date now depends on two things: how quickly the EIP-8037 review ends, and whether the EIP changes as a result. If the gas rules change, clients would need new releases and would likely have to be tested again. That review also overlaps with the EIP's November 1 Last Call deadline.

Glamsterdam is more than a gas update. It also includes enshrined proposer-builder separation (ePBS), a new way of choosing block builders, and block-level access lists, which help clients process larger blocks. Both are part of Ethereum's push to raise the gas limit. Separate design debates are still going on. Our explainer on the four-minute fast-finality proposal covers a different change, EIP-8453, which is not part of this delay.

For smart contract teams, the practical message is to check code that depends on remaining gas after an external call, on fixed gas amounts, or on retry logic, and to follow ChainSecurity's disclosures and the EIP discussion. For everyday users, nothing changes on mainnet for now. Readers following the wider market can see our crypto daily brief, and those who hold assets themselves can read our guide on how to secure a crypto wallet seed phrase.

What is still unknown

• When Glamsterdam will be rescheduled on Hoodi, and whether the 200 million gas limit increase will come at the same time.
• Whether EIP-8037 or EIP-8038 will be changed, and how.
• Which of the 13 contracts ChainSecurity reported are affected, and whether their teams will need to redeploy or patch.
• Whether a December mainnet date is still realistic.

Sources

• Ethereum Foundation Blog: Glamsterdam on Hoodi postponed (October 22, 2026)
• EIP-8037: State Creation Gas Cost Increase (eips.ethereum.org)
• CoinDesk: Ethereum delays Glamsterdam test after security devs flag risk to existing contracts
• crypto.news: Ethereum Glamsterdam Hoodi upgrade postponed
• Ethereum Research: Failure modes in EIP-8037 and state-gas scaling

This article is for information only and is not investment advice.