Ethereum developers, fresh off last month’s successful Fusaka upgrade that lowered node costs, are already full steam ahead planning the blockchain’s next major change.
Enter “Glamsterdam.”
The name is an acronym for two simultaneous updates that take place on the two core layers of Ethereum. The execution layer, where transaction rules and smart contracts reside, will undergo the Amsterdam update, while the consensus layer, which coordinates validators and finalizes blocks, will see an update known as Gloas.
Enshrined in the heart of Glamsterdam is the Proposer-Builder Separation (ePBS), formally tracked as EIP-7732. The proposal would include in Ethereum’s core protocol a rule that separates the nodes that build blocks from those that propose them, preventing a single actor from controlling which transactions are included or how they are ordered.
Today, this separation relies heavily on off-chain services known as relays, which introduces trust assumptions and centralization risks. Under ePBS, block builders would assemble blocks and cryptographically seal their contents, while proponents would simply choose the highest-paying block without being able to see or alter what’s inside. Transactions would only be revealed after the block is finalized, reducing opportunities for manipulation and abuse related to MEV, or maximum extractable value – the additional profits that validators or builders can make by reordering, inserting or censoring transactions.
Another proposal slated for Glamsterdam is Block-Level Access Lists (EIP-7928), a hidden change that allows a block to declare in advance which accounts and smart contract data it will access. Instead of discovering this information on a transaction-by-transaction basis, Ethereum software (known as clients) can preload and reuse data more efficiently, making block execution faster, more predictable, and easier to optimize. The change could help smooth gas costs and lay important foundations for future scale improvements.
Both ePBS and block-level access lists are examples of Ethereum improvement proposals, or EIPs, which are formal proposals that outline changes to the protocol and serve as the primary coordination mechanism for the Ethereum development process.
The full scope of Glamsterdam has not yet been finalized and additional EIPs are expected to be selected in the coming weeks. As for timing, the developers haven’t committed to a specific date, but have indicated that the update will likely come sometime in 2026.
Read more: Ethereum activates Fusaka upgrade, aiming to reduce node costs and accelerate layer 2 agreements
