Upgrade Overview
Glamsterdam is set to be Ethereum's largest network upgrade since The Merge, scheduled for the second half of 2026. The core improvements include in-protocol PBS (ePBS) to eliminate reliance on relayers, Block-Level Access Lists (BALs) enabling parallel execution and efficient synchronization, and a repricing of gas to more accurately reflect computation and state storage costs. These changes are designed to enhance mainnet performance, stabilize transaction fees, and maintain decentralization.
With ePBS, the upgrade removes the need for external relayers in proposer-builder separation, reducing trust assumptions and potential MEV concentration. BALs allow the network to process transactions in parallel rather than sequentially, improving throughput and state access efficiency. The gas repricing mechanism adjusts fee calculation to better account for the actual resource consumption of each operation, leading to more predictable gas costs for users. Overall, Glamsterdam addresses key scalability and fee predictability challenges while preserving Ethereum's core values of decentralization and security.