Ethereum developers have postponed the Glamsterdam upgrade on the Hoodi testnet, cancelling the activation that had been scheduled for October 26 at 17:42:48 UTC, corresponding to Hoodi epoch 132,352. The Ethereum Foundation confirmed the decision after an All Core Developers Execution meeting, citing the need to investigate how EIP-8037 gas accounting changes interact with existing mainnet smart contracts.
The postponement removes the planned increase of Hoodi’s gas limit to 200 million. The Foundation said this adjustment affects a future network upgrade and does not reverse Hoodi’s existing transaction history. Ether users and mainnet holders do not need to take action, but application developers have been told not to plan further Hoodi testing around the canceled October 26 activation.
Security firm ChainSecurity warned that the proposed changes could alter how deployed smart contracts handle unsuccessful external calls. Some applications use remaining gas balances to determine whether an operation failed permanently or should remain eligible for retry. Under the proposed rules, a failed operation could leave enough gas for the calling contract to continue processing when the same transaction would previously have reverted. ChainSecurity said it had found 13 real-world examples of potentially affected contracts and is engaged in responsible disclosure with affected projects.
The revisions also touch EIP-8038, which changes costs associated with accessing existing state, and raised concern around batched transactions, withdrawals and failure-handling mechanisms. Ethereum researcher Christine D. Kim warned Hoodi node operators that the Monday upgrade had been canceled and advised them to revert to older software versions or install updated clients that remove the scheduled fork.
The Foundation’s revised release table lists Lodestar v1.50.1 for the consensus layer, with execution-layer releases including Besu 26.10.1 and Nethermind 2.2.1. Ethrex v30.0.1-rc.2 appears as a prerelease. Validator operators must check beacon nodes, validator clients and any external block-building infrastructure.
Ethereum’s Glamsterdam activation on Sepolia proceeded on October 6, allowing developers to examine the upgrade with a higher gas limit. The Hoodi postponement concerns a separate testnet and does not reverse the earlier Sepolia activation. Before the delay, developers had discussed December 1, December 8 and December 9 as possible mainnet activation dates, but none were confirmed. Replacement Hoodi and mainnet dates remain undecided.
The delay reflects a cautious approach to Ethereum’s roadmap as developers assess smart contract compatibility and security before selecting a new testnet or mainnet schedule.
