The Ethereum core developer community has officially scheduled the upcoming Glamsterdam network upgrade for the Hoodi testnet. This major developmental milestone follows closely on the heels of the upgrade’s successful initial activation on the Sepolia testnet, which took place earlier this month on October 6, 2026.
As the next critical phase in Ethereum’s Layer 1 scaling roadmap, the Glamsterdam upgrade introduces a sweeping array of foundational protocol enhancements. These changes span enshrined proposer-builder separation, block-level access lists, and comprehensive adjustments to gas pricing mechanisms designed to more accurately reflect the true costs of transaction execution and long-term state growth.
Glamsterdam Activation Details for Hoodi
According to the agreed deployment schedule confirmed in the Hoodi network configuration, the Glamsterdam network upgrade is scheduled to activate on the Hoodi testnet at epoch 132,352, corresponding to slot 4,235,264. The activation event is timed precisely for October 26, 2026, at 17:42:48 UTC.
Simultaneously at this activation epoch, the gas limit on the Hoodi testnet will be raised to 200 million, bringing it in line with the parameters established during the Sepolia deployment. While testnet testing is progressing rapidly, a definitive activation date for the Ethereum mainnet has not yet been finalized by client teams and will be announced at a later date once client stability is thoroughly verified.
In preparation for the upcoming transition, node operators are instructed to update both their execution layer and consensus layer clients to compatible versions as they are released and confirmed. Running updated software is mandatory, as nodes operating on legacy software will not be able to follow the upgraded network rules once the activation threshold is crossed.
Overview of the Glamsterdam Upgrade
The Glamsterdam upgrade represents a unified overhaul of the Ethereum protocol, combining the Amsterdam execution layer upgrade with the Gloas consensus layer upgrade. Together, these complementary upgrades introduce structural changes aimed at significantly scaling Layer 1 throughput without compromising the decentralization or security of the network.
At the core of this upgrade are two major architectural overhauls: enshrined proposer-builder separation and block-level access lists. These features fundamentally transform how transaction blocks are constructed, proposed, and validated across the decentralized network, creating a more robust framework for future capacity expansions.
Enshrined Proposer-Builder Separation
Implementing EIP-7732, the upgrade brings the vital separation between block proposers and block builders directly into Ethereum’s core consensus protocol. Under this new framework, a block proposer includes a builder’s cryptographic commitment to an execution payload, and the builder subsequently reveals that payload in a timely manner. The protocol itself handles the payment mechanics directly to the proposer, significantly reducing the network’s reliance on trusted external middleware for the complex exchange of blocks.
This structural change also decouples consensus validation from execution validation, granting validators a dedicated window of time to properly validate execution payloads. To ensure reliability, a newly established payload timeliness committee will attest whether the builder successfully revealed its payload and whether the corresponding blob data was made available on schedule. Validator operators and teams maintaining builder infrastructure are strongly advised to review these new protocol duties and interface requirements well ahead of the upgrade.
Block-Level Access Lists
To tackle the complexities of network scaling, EIP-7928 introduces enforced block-level access lists. These lists record the specific accounts and storage locations accessed over the course of a block, alongside the resulting post-transaction state changes.
By providing explicit visibility into state interactions, these access lists enable client software to read state data from disk in parallel, validate incoming transactions concurrently, and compute state roots with vastly improved efficiency. Combined with proposer-builder separation, block-level access lists establish a solid technical foundation for higher transaction throughput while keeping hardware and validation requirements practical for independent node operators.
Gas Pricing and State Growth Adjustments
Glamsterdam also introduces critical adjustments to gas accounting to better align transaction fees with actual resource consumption. EIP-8037 increases and separately meters the cost associated with creating new state, while EIP-8038 updates the baseline costs for accessing existing state data. Additional modifications cover intrinsic transaction gas parameters, calldata handling, access lists, and broader block gas accounting rules.
Application and smart contract developers are urged to thoroughly test their contracts and gas estimation logic against these revised economic rules. Contracts that rely on fixed gas stipends, hardcoded gas limits, or outdated assumptions regarding remaining gas may require code modifications to function correctly. Developers can consult the official Glamsterdam repricing impact guide and affected-contracts search tools for detailed testing guidance.
Developer and Validator Improvements
Beyond the headline scaling features, Glamsterdam incorporates several targeted improvements for developers and validators. These include the introduction of native ETH transfer logs, a new slot-number opcode, an increased maximum contract size limit, a deterministic factory contract, and advanced stack-manipulation instructions.
On the consensus side, changes include forward-compatible data structures, protocol-level rules to exclude slashed validators from proposing new blocks, and increased limits on validator exit and consolidation churn rates to ensure smoother network operations.
Security and the Ethereum Bug Bounty Program
The Ethereum Bug Bounty Program remains fully active for all specifications and EIPs associated with the Glamsterdam upgrade. Client implementations become eligible for bug bounty rewards as soon as their respective software releases are officially confirmed and integrated into the network release schedule. Security researchers and developers are encouraged to review the official Ethereum Bug Bounty Program documentation for details regarding reward multipliers, submission guidelines, and vulnerability reporting requirements.
Client Releases and Operator Responsibilities
Node operators running infrastructure on the Hoodi testnet must ensure they apply the necessary software updates prior to the October 26 activation timestamp. When operating a validator, both the consensus layer beacon node and the validator client must be updated simultaneously. Operators must verify that their chosen release notes explicitly confirm support for the scheduled Glamsterdam activation on Hoodi.
The upgrade process underscores the decentralized nature of Ethereum network maintenance. Network upgrades require explicit, voluntary opt-in from node operators worldwide, who coordinate protocol changes by updating their software implementations. Non-upgraded nodes will automatically diverge from the canonical chain once the upgrade takes effect, highlighting the importance of diligent upgrade coordination across the community. Mainnet users, ETH holders, and operators on networks other than Hoodi do not need to take any immediate action regarding this specific testnet announcement, as mainnet activation timelines will be communicated separately once testnet validation is complete.
Ethereum & Smart Contracts
Ethereum & Smart Contracts
Ethereum & Smart Contracts
