Ethereum Prepares for Glamsterdam Network Upgrade as Hoodi Testnet Activation is Officially Scheduled

Ethereum’s upcoming major network upgrade, dubbed "Glamsterdam," is continuing its methodical path toward deployment with a newly announced activation schedule for the Hoodi testnet. Following its successful rollout on the Sepolia testnet earlier in October 2026, developers and core contributors have locked in the specifications to bring the extensive layer-one scaling package to Hoodi. The upgrade is set to go live at epoch 132,352 and slot 4,235,264, which corresponds to October 26, 2026, at 17:42:48 UTC. Alongside this activation, the Hoodi testnet will experience a significant adjustment, raising its gas limit to 200 million to align with testing parameters previously established on Sepolia. While testnet timelines are steadily materializing, core developers have noted that an official mainnet activation date has not yet been finalized and will be determined once testnet stability is thoroughly evaluated.

The Glamsterdam upgrade represents a major milestone in Ethereum’s evolution, combining the Amsterdam execution layer upgrade with the Gloas consensus layer upgrade. Together, these complementary packages introduce sophisticated changes designed to enhance the network’s foundational throughput, optimize block production, and modernize state management. Among the headlining improvements are enshrined proposer-builder separation and block-level access lists, both of which target long-standing bottlenecks in how transactions are organized, validated, and executed across decentralized nodes.

At the core of the consensus modifications is enshrined proposer-builder separation, formalized under EIP-7732. This protocol-level adjustment integrates the separation of block proposers and block builders directly into Ethereum’s consensus mechanism, minimizing reliance on trusted off-chain middleware. Under the new architecture, a block proposer includes a builder’s commitment to a specific execution payload within a slot, and the builder subsequently reveals the payload. The protocol autonomously manages the financial settlement and payments owed to the proposer. Furthermore, the architecture decouples consensus validation from execution validation, granting validators crucial extra time to review execution payloads. A specialized payload timeliness committee will oversee the process, attesting whether builders successfully reveal their payloads and ensure that associated blob data is disseminated punctually.

Complementing the consensus shifts are block-level access lists introduced via EIP-7928. These enforced lists systematically record the accounts and storage locations accessed over the course of a single block, packaging them alongside post-transaction state changes. By providing explicit visibility into state interactions before full execution, client software can read state data from disk concurrently, validate transactions in parallel, and compute state roots with vastly improved efficiency. Combined with enshrined proposer-builder separation, these features establish a robust foundation for scaling Ethereum’s execution capacity while ensuring that day-to-day validation remains computationally feasible for independent node operators.

In tandem with structural scaling changes, Glamsterdam introduces critical adjustments to gas pricing and resource accounting to combat state bloat. EIP-8037 increases and independently meters the financial cost associated with creating new network state, while EIP-8038 updates broader state-access costs. Additional modifications recalibrate intrinsic transaction gas parameters, calldata consumption, access lists, and overarching block gas accounting. These economic adjustments are carefully calibrated to ensure that the cost of execution and state growth accurately mirrors the underlying burden placed on hardware infrastructure. Application developers have been strongly encouraged to test their smart contracts and gas estimation logic against the new rules, particularly checking for legacy assumptions involving fixed gas stipends or hardcoded limits that could be impacted by the repricing framework.

Beyond core scaling and economic changes, the upgrade encompasses a wide array of developer and validator enhancements. These feature additions include native Ethereum transfer logs, a dedicated slot-number opcode, an elevated maximum contract size limit, a deterministic factory contract, and advanced stack-manipulation instructions. On the consensus side, protocol updates incorporate forward-compatible data structures, mechanisms to exclude slashed validators from the proposal queue, and adjustments to increase the overall exit and consolidation churn rate.

Security remains a top priority as the activation window approaches, with the Ethereum Bug Bounty Program maintaining active coverage for all Glamsterdam specifications and associated EIPs. Client implementations become officially eligible for bounty rewards as soon as their respective release candidates are formally published and integrated into network configurations. Node operators running infrastructure on Hoodi must ensure they update both their execution layer and consensus layer clients prior to the October 26 activation timestamp. Because network upgrades require explicit software opt-ins, non-compliant nodes will be unable to follow the upgraded chain after the transition epoch occurs.

While mainnet users and standard ETH holders do not need to take any direct action for the Hoodi testnet deployment, node operators, stakers, and tooling providers are urged to review client release notes carefully to ensure full compatibility. As development teams continue to monitor testnet performance leading up to the end of October, community members can look forward to further announcements regarding the timeline for the mainnet activation of Glamsterdam.