Ethereum developers have put the Glamsterdam upgrade on the Hoodi testnet on hold after security researchers identified eight smart contract assumptions that could become invalid under proposed gas accounting changes. In a November 6 blog post, the Ethereum Foundation said auditing firm ChainSecurity found that EIP-8037 and EIP-8038 would alter how gas is charged for creating and accessing blockchain state, potentially affecting existing contracts that depend on fixed gas costs or specific transaction failure conditions.
The postponement removes the Amsterdam execution-layer and Gloas consensus-layer activations from Hoodi, originally scheduled for October 26 at 17:42:48 UTC. No replacement activation date has been announced. ChainSecurity warned that some contracts depend on assumptions such as gas consumption moving only in one direction, fixed gas allowances remaining sufficient, or reverted calls not returning gas already spent on creating state. Under Glamsterdam's revised accounting, previously unavailable gas could become accessible after a failed call, allowing operations to finish when developers originally expected the entire transaction to revert and potentially weakening failure safeguards.
Ethereum Foundation developer Marius van der Wijden said the organization is working with ChainSecurity and Dedaub while conducting internal audits. The Foundation has asked developers, auditors, wallets, relayers, and other off-chain infrastructure operators to review affected code and report issues before the next All Core Developers discussion. Depending on feedback, developers may consider adjustments to EIP-8037 and EIP-8038 before proceeding with the upgrade.
Glamsterdam had already activated on the Sepolia testnet on October 6, where developers began examining its scaling changes under a 200 million gas limit. The upgrade introduces enshrined proposer-builder separation through EIP-7732, block-level access lists through EIP-7928, and gas repricing through EIP-8037 and EIP-8038. Development of Ethereum's subsequent Hegota upgrade continues without interruption.
