Ethereum’s planned Glamsterdam network upgrade will not activate on the Hoodi testnet until developers resolve compatibility risks with existing smart contracts, according to a November 6, 2026, post by Ethereum Foundation researcher Marius van der Wijden.
The upgrade, already running on the Sepolia testnet since October 6, had been scheduled for Hoodi on October 26 at epoch 132,352.
Core developers postponed that activation during the All Core Devs Execution call #248 on October 22 after security analysis raised concerns about how proposed gas-accounting changes interact with deployed contracts.
The October 22 Ethereum Foundation announcement confirmed that both the execution-layer (Amsterdam) and consensus-layer (Gloas) activations, along with a concurrent gas-limit increase to 200 million on Hoodi, were removed from the schedule pending further review. No replacement date was set.
The issues center on EIP-8037 (State Creation Gas Cost Increase) and EIP-8038 (State-Access Gas Cost Update), both scheduled for inclusion in Glamsterdam under the meta-EIP-7773.
These proposals reprice and restructure gas charges for creating and accessing blockchain state.
EIP-8037 raises the cost of new accounts, storage slots, and contract deployments, meters those costs separately through a state-gas “reservoir” for transactions exceeding 16,777,216 gas, and allows certain refunds or restorations of state gas mid-transaction.
EIP-8038 increases costs for accessing existing state to better match real-world performance on Ethereum’s larger state size.
Together they aim to support higher throughput and larger gas limits while controlling state growth, which is a prerequisite for Layer-1 scaling features such as enshrined proposer-builder separation (EIP-7732) and block-level access lists (EIP-7928).
ChainSecurity’s October 13 analysis, “Glamsterdam Hard Fork: When Spent Gas Comes Back,” showed that these rules can invalidate assumptions many contracts make about gas behavior.
In particular, gas that was previously spent can be restored after a failed or reverting call, gasleft() can increase during a transaction, and the cost of certain operations rises sharply.
As a result, failure-handling paths that once reverted can now complete, potentially turning a retryable out-of-gas condition into a permanent recorded failure.
This weakens defenses against insufficient-gas griefing, in which an attacker supplies just enough gas for a contract to log a failure but not enough for the intended operation to succeed.
The firm noted that even unchanged contract code can behave differently after the upgrade.
The Ethereum Foundation’s November 6 post states that All Core Developers therefore decided not to proceed with the Hoodi fork until the issues are resolved.
Work on the subsequent Hegotá upgrade continues in parallel.
To support a pragmatic decision on the next All Core Devs calls, the Foundation is engaging ChainSecurity and Dedaub for audits, conducting internal reviews, and issuing a public call to action.
Developers and auditors are asked to examine their projects against eight specific invariants that EIP-8037 and EIP-8038 will break.
These are documented in the public repository ethereum/glamsterdam-gas-invariants, which includes explanations, code red flags, example impacts, and suggested fixes.
Most observed findings so far relate to fixed gas budgets and reserves (INV-4 and INV-7).
Affected projects are requested to contact glamsterdam@ethereum.org with details, preferably including a working demonstration, so that any necessary specification adjustments can be considered before further progress toward mainnet.
Glamsterdam remains one of the major steps in Ethereum’s Layer-1 scaling roadmap. The current pause on Hoodi gives the ecosystem time to identify and address contract-level incompatibilities that gas repricing can introduce, before the changes move closer to production. No mainnet activation date has been set.
