The much-anticipated Glamsterdam upgrade on the Ethereum network has reached its final development phase, marking a pivotal point in the protocol’s evolution. Core developers are now focusing on rigorous testing within dedicated private networks, simulating all protocol changes before taking the next step. In the coming weeks, the teams are expected to finalize stress tests and begin trials on public testnets, a critical move before mainnet integration.
Final stage testing advances
Parithosh Jayanthi, a core developer and DevOps engineer at the Ethereum Foundation, confirmed that engineering teams are currently working with devnets that include every Ethereum Improvement Proposal (EIP) targeted for Glamsterdam. Jayanthi emphasized that this is the last checkpoint for internal testing ahead of the public test phase. The Ethereum Foundation continues to play a central role in supporting research and technical development for the ecosystem.
Parithosh Jayanthi explained that teams are operating within devnets containing all the proposed protocol updates, with the next phase focused on boosting the system’s resilience before rolling out to testnets.
While an official launch date for the upgrade has yet to be set, current expectations suggest that Glamsterdam could be deployed on the mainnet during the second half of 2026.
Most significant change since the Merge
Describing Glamsterdam as the most substantial hard fork since the Merge, Jayanthi highlighted the magnitude of this technical overhaul. Recall that the September 2022 Merge saw Ethereum transition from proof of work to a proof of stake model. The forthcoming upgrade will introduce transformative changes to the network’s foundational protocol, potentially paving the way for greater scalability and efficiency in the future.
Glamsterdam follows the Fusaka upgrade, which was activated in December 2025. Whereas Fusaka focused on core protocol enhancements, Glamsterdam is more ambitious—tackling key architectural elements to unlock broader changes across the Ethereum network.
Three major technical shifts in focus
One of Glamsterdam’s standout features will be the enshrined Proposer Builder Separation (EIP 7732). This reform brings the block proposing and building process directly into the protocol layer, addressing major concerns around dependence on trust and mitigating risks linked to MEV, which have arisen from the process being largely outside the core protocol until now.
Quick glossary: MEV (Maximal Extractable Value) refers to the extra revenue gained by reordering transactions during block production. Proposer Builder Separation seeks to clarify roles between the validator proposing the block and the entity building it, streamlining the process and enhancing security.
Another significant development is the introduction of block-level access lists via EIP 7928. This enables blocks to announce in advance which account states and smart contract data they’ll require, letting clients preload and cache information. The result: faster validation and less need for dynamic data queries during block execution.
The third core change involves a sweeping revamp of the gas fee model. Under the proposed system, transactions demanding high computational power are set to become cheaper, while on-chain data storage will become more expensive. This adjustment is also designed to boost compatibility with popular zero-knowledge proof systems widely used in current Layer 2 solutions.
Jayanthi emphasized that this update will significantly alter transaction costs on Ethereum: compute-heavy operations will become much less expensive, while maintaining state will come with a higher price tag.
At present, developers are finalizing technical specifications, carrying out broad-based tests, and assessing how these pricing changes will impact users and app developers. The roadmap charts a clear progression from private test environments to public testnets, culminating with the highly anticipated mainnet launch.
