Ethereum developers initiate private testing for Glamsterdam upgrade

The upgrade represents a significant shift in protocol architecture, described by Ethereum Foundation developer Parithosh Jayanthi as the most substantial change since The Merge. At its core, the update introduces Enshrined Proposer-Builder Separation (EIP-7732) to integrate the split between builders and proposers directly into the protocol, aiming to minimize reliance on off-chain relays and mitigate risks associated with maximal extractable value.

Alongside ePBS, the upgrade implements Block-Level Access Lists (EIP-7928). By requiring blocks to declare which accounts and contract data they will interact with ahead of execution, the protocol allows nodes to pre-load information and process transactions in parallel. This structural optimization is paired with a recalibration of gas pricing. According to Jayanthi, the new fee structure will lower costs for compute-heavy actions while increasing the expense for state storage, forcing developers to rethink contract design to better align with actual network resource consumption.

While the roadmap for 2026 remains fluid, the success of these private devnets will determine the timeline for public deployment. For the broader user base, the transition will be largely invisible, requiring no action regarding wallets or assets. However, node operators and validators must prepare for mandatory client software updates once the mainnet activation date is finalized.