Glamsterdam is an upcoming major network upgrade for the Ethereum blockchain, designed to enhance its scalability, security, and sustainability. It is the proposed Execution Layer (EL) upgrade following the Fusaka upgrade, focusing on gas optimizations and protocol-level efficiency improvements. The name "Glamsterdam" is derived from combining the star Gloas with Amsterdam, the city where a recent Devconnect event took place. ^[1]

Overview

Glamsterdam represents a crucial phase in Ethereum's ongoing evolution, aiming to address persistent challenges such as network scalability and high transaction fees. This upgrade is part of a broader roadmap that includes previous milestones like the Pectra and Fusaka upgrades, all contributing to Ethereum's long-term vision as a global computing platform. The Ethereum Foundation has reorganized its research and development division into "Protocol," a leaner and more focused entity led by veterans like Tim Beiko and Ansgar Dietrichs. This reorganization prioritizes scaling the Layer 1 (L1), expanding blobspace, and improving user experience (UX), mandates that directly align with the anticipated priorities of Glamsterdam.

The development approach for Glamsterdam emphasizes stability and thorough testing, reflecting the iterative nature of blockchain development. This commitment ensures that new features are robust and well-integrated into the network's broader roadmap. The successful implementation of Glamsterdam is expected to significantly impact the entire Ethereum ecosystem, benefiting investors through enhanced network efficiency, developers through new functionalities and tools, and users through a more stable, secure, and cost-effective experience. ^{[2] [3] [7]}

Naming Convention

Ethereum network upgrades traditionally derive their names from various sources, often combining a star name for the Consensus Layer (CL) upgrade with a city name for the Execution Layer (EL) upgrade. Historically, Devcon cities were used for naming upgrades. However, with Devcon becoming a biennial event, the use of Devconnect city names, such as Amsterdam, has been adopted for annual upgrades. For Glamsterdam, the name combines "Gloas," a G-star, with "Amsterdam," the city that hosted a recent Devconnect event. This naming convention is part of a Meta Ethereum Improvement Proposal (EIP-7773: Hardfork Meta - Amsterdam). ^[1]

Development Roadmap

The Glamsterdam upgrade is positioned as the successor to the Fusaka upgrade, which is tentatively scheduled for mainnet deployment in early November 2025. Ethereum core developers have outlined a detailed roadmap for Glamsterdam, encompassing several critical phases from feature selection to mainnet activation. This structured approach aims to ensure a smooth and secure transition for the network. ^{[4] [5]}

Headliner Selection Phase

The initial phase involves the selection of "headliner" features that will define Glamsterdam's primary focus. Client teams have been actively discussing and narrowing down potential Ethereum Improvement Proposals (EIPs) for inclusion. As of late July and early August 2025, leading candidates include Block-Level Access Lists and Fork-Choice Inclusion Lists (FOCIL). These proposals aim to enhance Layer 1 (L1) scanning efficiency or improve state-bloat resilience, shaping the thematic direction of the upgrade. ^[4]

Proposal Deadline and Specification Freeze

To prevent scope creep and ensure timely progress, a strict deadline has been set for finalizing headliner choices and submitting regular EIPs. This cut-off, set for August 21, 2025, allows developers to merge, audit, and document all included EIPs before the network enters the rigorous testing phase. This disciplined approach is crucial for managing the complexity of a major blockchain upgrade. ^[4]

Testing and Audit Windows

The rollout process for Glamsterdam will commence with the creation of dedicated client release branches in late 2025, mirroring the frozen specifications. In early 2026, one or more public testnets are planned to be launched. These testnets are vital for identifying interoperability issues under realistic network conditions and for broader community participation, allowing dApp developers, node operators, and researchers to test their applications and infrastructure against the new changes. Following the testnet phase, two 30-day windows are allocated for security audits and community bug hunts, a model successfully employed during the Fusaka upgrade. This comprehensive testing and auditing process is designed to ensure the network's resilience and gather essential developer feedback before committing to mainnet activation. ^{[3] [4]}

Key Features

While still in its early design stages, Glamsterdam is expected to introduce several significant improvements to the Ethereum network. A primary focus of the upgrade is the transition from Merkle trees to Verkle trees. This change is anticipated to enhance how Ethereum stores data and validates transactions, paving the way for greater scalability and efficiency. Verkle trees are a critical component of Ethereum's "The Verge" phase, which aims to make state access more efficient and enable stateless block verification.

Other potential EIPs and features under consideration for Glamsterdam include:

• EIP-7732 (ePBS - enshrined Proposer-Builder Separation): This proposal aims to enable pipelined block validation, which can reduce the load on network nodes and improve overall efficiency.
• EIP-7805 (FOCIL - Fork-Choice Inclusion Lists): FOCIL is designed to introduce stronger user experience (UX) and enhance censorship resistance within the network.
• Gas Optimizations and Protocol-Level Efficiency: Glamsterdam will focus on making Ethereum faster and cheaper to use, particularly for complex applications like Layer-2 rollups and zero-knowledge (ZK) technology.
• EIP-7907 (Contract Code Size Limits): Although deferred from the Fusaka upgrade to prioritize stability, a revised version of EIP-7907, which addresses contract code size limits and introduces gas metering, is being considered for future implementation in Glamsterdam. This deferral highlights the developers' commitment to thorough testing over rushed deployment.
• Reduced Block Time: Ethereum core developer Barnabé Monnot has proposed reducing the block time from the current 12 seconds to 6 seconds. If approved, this change could significantly improve user experience and enhance the efficiency of decentralized finance (DeFi) applications. This proposal is being considered for rollout with the Glamsterdam hard fork. ^{[1] [2] [3] [5] [6]}

Impact and Challenges

The successful implementation of Glamsterdam is expected to have a profound impact across the Ethereum ecosystem. For investors, successful upgrades can enhance network efficiency and utility, potentially increasing the long-term value proposition of Ethereum (ETH). Smooth transitions build confidence in the network's future, signaling a robust and well-managed platform. For developers, new EIPs introduce new functionalities, tools, and optimizations, enabling the creation of more sophisticated, efficient, and secure decentralized applications. This fosters innovation and expands the possibilities within the Ethereum ecosystem. For users, while direct changes might not always be immediately apparent, upgrades contribute to a more stable, secure, and potentially faster and cheaper network experience over time. This translates to better dApp performance and reduced transaction costs, making the network more accessible and user-friendly.

Despite the anticipated benefits, blockchain development, particularly for a network as large and complex as Ethereum, presents significant challenges. Coordinating thousands of developers globally, ensuring backward compatibility, and rigorously testing every change is a monumental task. The decision to defer EIP-7907 from Fusaka underscores this complexity, demonstrating the developers' commitment to caution and thoroughness over rushed implementation, prioritizing the network's integrity. A key challenge is also ensuring that as Ethereum scales, it preserves its core ethos, including censorship resistance and privacy, which some developers have raised concerns about if not explicitly reaffirmed as strategic goals.

Tim Beiko, a project coordinator, stated, "Protocol is now a more united and leaner organization with more focused teams…ensuring the EF’s resources are allocated toward maximal impact." He also noted, "Ethereum stands at the edge of major breakthroughs…This may be our best shot at deploying not only our technology, but our values, at planetary scale." Ansgar Dietrichs added, "For Glamsterdam…we will have to find some ways to continue the blob scaling…there might be some EL-side scaling opportunities too." These statements highlight the strategic importance and ambitious goals of the Glamsterdam upgrade. ^{[2] [3]}