Ethereum Network Upgrade: The Glamsterdam Activation and Its Strategic Impact on Layer 1 Scaling

The Ethereum network is preparing for the highly anticipated Glamsterdam upgrade, a pivotal technical milestone designed to advance the protocol’s Layer 1 scaling roadmap by introducing enshrined proposer-builder separation (ePBS) and block-level access lists (BALs). Building on the momentum of the previous Fusaka upgrade, which took place in late 2025, Glamsterdam represents a significant shift in how Ethereum handles execution, validation, and state management. The upgrade is scheduled to activate on the Sepolia testnet at epoch 353,024, slot 11,296,768, which corresponds to October 6, 2026, at 13:53:36 UTC. While this announcement provides critical deployment details for the testnet environment, the timeline for the Hoodi and mainnet activations remains subject to further coordination among core developer teams.

The Glamsterdam upgrade serves as a hybrid evolution of the network’s architecture, merging the Amsterdam execution layer improvements with the Gloas consensus layer enhancements. By modernizing the interaction between block proposers and builders, the Ethereum Foundation and the broader developer community aim to increase the network’s throughput while simultaneously refining the cost structure of state growth and execution.

Architectural Foundations: ePBS and Block-Level Access Lists

At the heart of the Glamsterdam upgrade lies the implementation of EIP-7732, which formalizes Enshrined Proposer-Builder Separation (ePBS) within the Ethereum consensus protocol. Historically, Ethereum has relied on off-protocol, trusted middleware—such as MEV-Boost—to manage the complex process of block construction. By bringing this functionality directly into the consensus layer, the protocol can now handle the exchange of execution payloads more securely and transparently.

Under this new framework, a block proposer includes a commitment from a builder to an execution payload, and the builder is subsequently required to reveal that payload. This protocol-level integration provides several advantages: it mitigates the reliance on third-party relayers, reduces the risk of censorship or manipulation at the builder level, and improves overall network resilience. Furthermore, the decoupling of consensus validation from execution validation is a critical change. It provides validators with additional time to verify execution payloads, ensuring that the network remains robust even as block complexity increases. To support this, a new “payload timeliness committee” will be introduced, tasked with attesting to the availability of the builder’s payload and associated blob data, thereby ensuring that the block remains valid and accessible within the required timeframes.

Complementing ePBS is EIP-7928, which introduces mandatory block-level access lists (BALs). These lists serve as a record of all accounts and storage locations accessed during the execution of a block, alongside the resulting post-transaction state changes. From an engineering perspective, the implementation of BALs allows client software to process state reads and transaction validations in parallel rather than sequentially. This is expected to significantly improve the efficiency of state root computation and disk I/O operations, providing a more scalable foundation for node operators to handle increased transaction volumes without compromising decentralization.

Adjusting the Economic Model: Gas Pricing and State Growth

As Ethereum continues to scale, managing the cost of state storage has become a primary concern for the network’s long-term sustainability. The Glamsterdam upgrade introduces comprehensive adjustments to gas accounting via EIP-8037 and EIP-8038. These EIPs refine how the network prices resource usage, specifically targeting the cost of state creation and access. By increasing and separately metering the cost of creating new state entries, the protocol aims to discourage state bloat, which has historically pressured the storage requirements for node operators.

For developers and smart contract engineers, these changes necessitate a proactive approach to testing. Contracts that rely on fixed gas stipends, hardcoded gas limits, or legacy assumptions about remaining gas availability may face unexpected failures or performance degradation. The Ethereum community has released a specific “Glamsterdam Repricing Impact Guide,” which provides tools for developers to scan their codebase for affected contracts and adjust their gas estimation logic accordingly. This period of transition highlights the importance of the testnet phase; by deploying to Sepolia first, developers gain a critical window to identify breaking changes in a low-risk environment before the mainnet activation occurs.

A Chronology of the Development Cycle

The path to Glamsterdam has been defined by a rigorous cycle of research, implementation, and collaborative testing. Following the successful deployment of the Fusaka mainnet upgrade in November 2025, the core developer community shifted its focus toward the technical challenges of enshrined proposer-builder separation. The specifications for Glamsterdam were finalized over several months, with EIP-7773 acting as the primary tracking document for the entire upgrade suite.

The following table summarizes the scheduled activation for the Sepolia network:

The decision to limit the initial rollout to Sepolia is consistent with Ethereum’s established governance model. By isolating the activation to a testnet, the foundation ensures that client software—including major execution and consensus clients—functions as intended under real-world, albeit simulated, network conditions. Once the Sepolia activation is deemed successful, and once client teams have achieved sufficient stability across their software releases, discussions regarding the Hoodi and mainnet schedules will commence.

Validator and Node Operator Requirements

For node operators and stakers, the Glamsterdam upgrade is not a passive event. It requires an active update of both the execution layer (EL) and consensus layer (CL) clients. As the network transitions to ePBS, validators must be particularly vigilant regarding their infrastructure setup.

Prysm and Teku, two of the most widely used consensus clients, have already released versions that include support for the Sepolia fork. However, these releases contain specific configurations that operators must be aware of. For instance, both clients default to a 60M gas limit post-activation, despite the protocol allowing for a 200M gas limit. Validators wishing to propose with the higher limit must explicitly configure their settings using the new proposer-builder API or relevant CLI flags. Failure to update these settings correctly could result in suboptimal block proposals or missed opportunities to capture the benefits of the new throughput capacity.

Furthermore, the upgrade introduces changes to the duties of validators, specifically regarding builder registration and the new communication interfaces required for ePBS. Stakers are strongly encouraged to review the updated technical documentation for their specific client implementations. The Ethereum Foundation has emphasized that the beacon node and the validator client must be updated in tandem to ensure seamless synchronization during the epoch transition.

Broader Implications and Future Outlook

The Glamsterdam upgrade is not merely a collection of technical patches; it represents a strategic evolution in the philosophy of Ethereum’s design. By enshrining core components like proposer-builder separation, the community is moving toward a “trust-minimized” architecture that reduces the influence of centralized intermediaries. This aligns with the long-term vision of a modular, scalable, and decentralized Ethereum that can support a growing ecosystem of L2 networks and decentralized applications.

From an analytical perspective, the shift toward parallelized execution via BALs and the recalibration of gas costs signify that Ethereum is prioritizing long-term hardware efficiency. As the state size of the blockchain continues to expand, the ability of node operators to maintain the network using consumer-grade hardware remains a cornerstone of Ethereum’s value proposition. By optimizing how state is accessed and stored, Glamsterdam ensures that the network remains accessible to a wider range of participants, thereby reinforcing the decentralization that is critical to the network’s security model.

The name "Glamsterdam" itself—a portmanteau of the consensus layer upgrade "Gloas" and the execution layer upgrade "Amsterdam"—serves as a reminder of the global nature of Ethereum’s development. The choice to name the upgrade after the city of Amsterdam, which hosted the 2022 Devconnect conference, reflects the community-driven ethos that continues to power the project.

Final Preparations for the Community

As the October 6, 2026, deadline approaches, the focus for the broader Ethereum ecosystem remains on readiness and security. The Ethereum Bug Bounty Program has been fully extended to cover the Glamsterdam specifications, with reward multipliers offered for identifying vulnerabilities in the new implementation.

For the average ETH holder or decentralized finance (DeFi) user, the upgrade requires no direct action. The network’s transition will be handled by node operators and validators. However, for the developer community, the coming weeks are critical. Testing on Sepolia should be treated as a dress rehearsal for the mainnet deployment. Those managing protocols that rely on complex smart contract interactions are encouraged to use the provided testing tools to identify potential conflicts with the new gas accounting rules.

In conclusion, the Glamsterdam upgrade represents a significant leap forward in Ethereum’s technical maturity. By integrating complex scaling solutions directly into the protocol, Ethereum continues to refine its ability to balance the competing demands of throughput, security, and decentralization. While the transition will require careful coordination and technical diligence, the long-term benefits—a faster, more efficient, and more resilient network—are expected to provide the foundation for the next generation of blockchain innovation. As the network prepares to go live on Sepolia, the eyes of the developer community are firmly fixed on the horizon, anticipating the next phase of the Ethereum roadmap.