Ethereum sets October 26 Hoodi test for Glamsterdam

Ethereum core developers agreed on October 8 to activate the Glamsterdam upgrade on the Hoodi testnet at 17:42:48 UTC on October 26, advancing the protocol package to its last planned public-testnet stage before any mainnet decision.

The decision came two days after Glamsterdam activated on Sepolia. It is a new testing milestone, not an Ethereum mainnet launch date. Client teams are targeting October 16 for Hoodi-compatible releases, leaving operators 10 calendar days between the release target and activation. That window is a coordination target established during the call, not a guarantee that every client will publish on time or that every operator will upgrade before the fork.

Hoodi broadens the operating test

Hoodi is Ethereum’s longer-lived test network for validator and staking-infrastructure testing. During the call, participants distinguished it from Sepolia: Hoodi includes a broader set of home stakers, staking pools and infrastructure operators, so a successful transition would test upgrade coordination across a more varied operator base.

The October 26 timestamp corresponds to Hoodi epoch 132,352 and start slot 4,235,264 in the scheduling proposal. The proposal remained marked as a draft when Coinburn checked it on October 9, although the meeting transcript and independent call recap both record developer agreement on the date. That procedural gap is important: the call established the target, while repository configuration and client releases still have to carry it into executable software.

Developers also set October 16 as the release target. One participant described the schedule as tight because Hoodi operators need time to deploy both execution-layer and consensus-layer clients. The group nevertheless kept October 26, partly to avoid pushing the test into travel surrounding Devcon. A late client fix or unresolved test failure could still force a schedule change.

What Glamsterdam changes

Glamsterdam combines changes to Ethereum’s execution and consensus layers. Its headline feature, enshrined proposer-builder separation, moves the exchange between block proposers and specialized builders into protocol rules. The package also introduces block-level access lists and revises gas accounting, state-access costs and other execution behavior.

Those changes affect more than validators. Wallets, indexers, gas estimators, smart-contract developers and external block builders may need to test assumptions about payload delivery, logs, gas use and state access. The Ethereum Foundation’s September announcement told application and tooling developers to test on Sepolia and review affected gas assumptions. Hoodi extends that work to a network with a different operating population.

A clean Sepolia fork supported the decision to proceed, but the call also exposed a limitation. Developers said builder participation on Sepolia was sparse and many blocks were built locally. That means Sepolia did not reproduce the full diversity or competitive conditions of Ethereum’s mainnet builder market. Hoodi can widen operational testing, but it still cannot prove how the upgrade will behave under mainnet load or economic incentives.

Mainnet remains unscheduled

The Foundation’s existing public announcement left both Hoodi and mainnet dates undecided. The October 8 call filled in the Hoodi target but did not approve a mainnet activation date. Dates discussed in planning material for December remain possibilities, not decisions.

The next verifiable steps are therefore mechanical: merge the Hoodi schedule, publish compatible client versions by the October 16 target, obtain operator uptake and observe the October 26 activation. Only after that testing and any resulting fixes can developers make a separate mainnet scheduling decision. For now, the evidence supports a testnet timetable—not a production upgrade, throughput promise or claim that Glamsterdam’s security and performance questions are settled.