Ethereum developers have canceled the October 26 Glamsterdam activation on the Hoodi testnet after concerns emerged about how proposed gas rules could affect existing smart contracts. The decision also suspends Hoodi’s planned increase to a 200 million gas limit. The Ethereum Foundation announced the change on October 22, following an All Core Developers Execution meeting. Developers have not set another activation date.
The review centers on EIP-8037, which changes how Ethereum accounts for gas used to create blockchain state. Developers now plan to examine its interaction with contracts already operating on mainnet before moving ahead with Hoodi testing.
The original schedule placed Glamsterdam’s activation at 17:42:48 UTC on October 26, during Hoodi epoch 132,352. In the revised configuration, developers removed the Amsterdam execution-layer activation and the Gloas consensus-layer activation.
They also withdrew the planned gas limit increase to 200 million. That change would have allowed developers to study higher capacity alongside other upgrades. The Foundation said the revision affects a future upgrade, not transactions already recorded on Hoodi. Its update gives no new date for Hoodi activation or the canceled gas limit test.
The decision reverses the schedule that developers had outlined earlier in October. Hoodi testing was intended to show how execution and consensus clients handled the protocol changes before the team chose a mainnet launch date.
Glamsterdam had already activated on the separate Sepolia testnet on October 6. That activation went ahead with a higher gas limit, and the Hoodi delay does not undo Sepolia’s earlier changes.
ChainSecurity detailed compatibility risks in an October 13 technical assessment. Its research examined EIP-8037 and EIP-8038, another proposal that revises the gas costs of accessing existing blockchain states.
Some deployed applications rely on the gas remaining after an external call to determine whether a failed operation can run again. New accounting rules could alter that result even though the contract code stays the same.
What happens when a failed call leaves enough gas for the calling contract to continue? ChainSecurity warned that some systems might record the failed action without giving users another chance to retry it.
Reports following the firm's public discussion described 13 real-world examples of potentially affected contracts. Researchers have not named those applications publicly, and responsible disclosure efforts continue. The concerns extend to batched transactions, withdrawals and other workflows that depend on existing failure checks. ChainSecurity also described how insufficient gas could disrupt safeguards without any edits to deployed contracts.
Following the cancellation, the Ethereum Foundation urged Hoodi node operators to review both execution and consensus clients before October 26. Operators must avoid software that still schedules the canceled fork.
Researcher Christine D. Kim advised operators to return to suitable older versions or adopt updated execution clients that remove the activation. The revised release table names Lodestar v1.50.1, Besu 26.10.1 and Nethermind 2.2.1.
It also lists Ethrex v30.0.1-rc.2 as a prerelease, while confirmation for other clients remains pending. Validators need to check beacon nodes, validator clients and any external block-building systems. Previously listed releases do not necessarily support the postponement.
Read More: Bitcoin & Ethereum Advance Separate Plans for Post-Quantum Wallet Security
Before this change, developers had considered December 1, 8 and 9 for a mainnet launch. None received final approval. The October 22 meeting agenda had proposed choosing a date the following week if Hoodi testing succeeded. The notice leaves the next activation dependent on further review. Glamsterdam also includes proposer-builder separation and block-level access lists intended to improve transaction processing.
Curve Finance previously pointed to possible DeFi benefits while flagging changing gas costs. For now, the Foundation says mainnet users and ETH holders need no action. Application teams should not schedule further Hoodi tests around October 26.
Ethereum has canceled Hoodi’s October 26 Glamsterdam activation and its planned 200 million gas limit while developers review contract compatibility risks. Node operators must adjust software to avoid the canceled fork. The Foundation has set no replacement date, and mainnet users need not take action.