Ethereum Foundation Sets Hoodi Activation of Ethereum (ETH) Glamsterdam Upgrade for October 27

Glamsterdam Reaches Hoodi on October 27

The Glamsterdam upgrade for Ethereum (ETH) goes live on the Hoodi testnet on October 27, at epoch 132,352 and slot 4,235,264, with the network's gas limit rising to 200 million in the same transition. The Ethereum Foundation set the schedule in an announcement published on October 16 and left the mainnet activation date open, making Hoodi the second public test network to carry the fork after Sepolia switched it on October 6. A slot is the roughly 12-second unit of consensus block time; pinning a fork to a fixed epoch and slot lets every client switch over in the same interval instead of drifting apart. An epoch contains 32 slots, so the published pair pins the fork moment to a fixed point on the chain's clock rather than a wall-clock estimate. What ships is a change to how blocks are proposed and checked, the mechanism the Foundation identifies as the route to expanding L1 processing capacity. The Foundation's notes describe Glamsterdam as the fork that reworks block production and block validation so the base layer can support higher throughput, the stated aim of the current Ethereum upgrade roadmap. The rollout follows the cadence earlier forks set, a sequence that runs back to the Ethereum 2.0 transition: code runs on test networks first, and a production date comes only after client teams confirm their releases. Every validator on Hoodi enforces the same fork rules at the same slot, which is what makes the activation a clean test of client readiness. The 200 million gas ceiling takes effect at activation rather than in a later tuning step, raising the per-block computation budget the chain works under. Testnet forks do not touch production funds, and the Ethereum price rarely reacts to them; the milestone that moves markets is a dated mainnet fork, which this announcement does not provide.

ePBS and Block Access Lists Lead the Change

The centerpiece is ePBS, specified in EIP-7732, which moves the split between the block proposer and the block builder into the protocol itself. The validator that proposes a block and the builder that assembles its contents already operate as separate roles on mainnet, but the handoff between them runs through intermediary software that assumes a degree of trust; EIP-7732 writes that handoff into the consensus rules, so the two sides interact through the protocol rather than a trusted middle layer. The Foundation names this one of the pillars of the change.

The second pillar, the block access list (BAL), is specified in EIP-7928. A BAL records every account and storage location a block touches, and with that record carried inside the block, client software can load state and verify transactions in parallel instead of one after the other. That parallelism is where execution gains stack on top of what ePBS changes. Pricing rules ride along in the same fork: EIP-8037 reprices state creation, metering the cost of new state separately from ordinary execution so nodes account for the data they must retain long term, and EIP-8038 updates the cost of accessing data. Both change the inputs behind a gas fee, and both can move numbers that deployed code depends on. That dependency shapes the workload. Node operators must update both the execution-layer and consensus-layer clients, and Hoodi-compatible versions will be added to the client release table as they are confirmed. Application developers face a different checklist: test contracts and gas estimates against the new rules, and review any smart contract that relies on a fixed gas stipend or a fixed gas ceiling, since the repricing can invalidate those assumptions. The Foundation has published guidance on locating affected contracts and on the test procedure, and our primer on never missing a hard fork covers the operator side of fork preparation in broader terms.

What Runs on Hoodi After October 27

Once the fork lands, Hoodi will run two things no Ethereum (ETH) network runs today: proposer-builder separation written into the consensus rules, and a block access list in every block. The staging order matches the pattern the Foundation has followed throughout, Sepolia on October 6 to prove the logic, Hoodi on October 27 to prove it under load, and a mainnet epoch as the one item still missing from the schedule. For node operators the practical anchor is the client release table, since the fork fires at a fixed slot and client readiness, not the calendar, decides whether the switch is clean. Glamsterdam stays a rehearsal until a mainnet epoch is named; from October 27, though, the code itself runs on Hoodi, and the production chain runs neither component.