The Ethereum core developer community has officially set the wheels in motion for the network’s next major milestone, dubbed the Glamsterdam upgrade. Following closely on the heels of the Fusaka mainnet announcement, Glamsterdam represents another significant leap forward in Ethereum’s Layer 1 scaling roadmap. The upcoming network upgrade introduces a powerful combination of systemic architectural improvements, most notably enshrined proposer-builder separation, block-level access lists, and a comprehensive overhaul of gas pricing designed to more accurately reflect the true costs of execution and state growth.
According to the official deployment schedule agreed upon by core developers and client teams, the Glamsterdam upgrade is officially scheduled to activate on the Sepolia testnet at epoch 353,024, which corresponds to slot 11,296,768. The activation is timed for October 6, 2026, at precisely 13:53:36 UTC, marking the first public testing milestone for the bundled package of Ethereum Improvement Proposals (EIPs). Meanwhile, activation timelines for other public testnets like Hoodi and the Ethereum mainnet remain undecided, with client teams expected to determine and announce those dates at a later stage once stability and performance on Sepolia have been thoroughly evaluated.
Ahead of the fast-approaching testnet deadline, node operators, stakers, and infrastructure providers are being urged to prepare early. Sepolia-compatible client versions are currently rolling out across the ecosystem, and node operators must ensure they update both their execution layer and consensus layer clients prior to the activation threshold. Using client software that lacks support for the incoming protocol rules will result in nodes dropping off the upgraded network, emphasizing the critical need for timely software upgrades across the independent operator base.
The Glamsterdam upgrade derives its name from a combination of the Amsterdam execution layer upgrade—paying homage to the host city of Devconnect in 2022—and the Gloas consensus layer upgrade, following the traditional convention of naming consensus upgrades after stars. By merging these two tracks, Glamsterdam tackles some of the most persistent bottlenecks in blockchain architecture, establishing a robust framework for long-term throughput expansion on Layer 1.
At the core of the upgrade are two headline specifications: enshrined proposer-builder separation and block-level access lists. Enshrined proposer-builder separation, specified under EIP-7732, directly integrates the traditionally off-chain division between block proposers and block builders into the core consensus protocol of Ethereum. Under this new mechanism, a block proposer includes a builder’s commitment to an execution payload within a slot, and the builder subsequently reveals the underlying payload. The protocol itself handles the payment mechanics directly to the proposer, significantly minimizing the reliance on trusted middleware and third-party relays that currently facilitate this exchange in the market.
Furthermore, this structural shift cleanly separates consensus validation from execution validation. By doing so, it affords network validators considerably more time to thoroughly review and validate execution payloads. To enforce accountability, a dedicated payload timeliness committee will attest whether the builder successfully revealed its payload and whether the corresponding blob data was made available on time. Validator operators, along with teams maintaining dedicated builder infrastructure, are strongly encouraged to review the updated protocol duties and interfaces well ahead of deployment.
Complementing ePBS is the introduction of block-level access lists under EIP-7928. This feature enforces systematic lists that record every single account and storage location accessed throughout the lifecycle of a block, alongside post-transaction state changes. For Ethereum clients, these structured lists unlock powerful performance optimizations, enabling software to read state from disk in parallel, validate incoming transactions concurrently, and compute state roots with vastly improved efficiency. Together, ePBS and block-level access lists lay the groundwork for expanding execution capacity while ensuring that running a validator or a standard node remains computationally practical for participants worldwide.
In addition to structural architectural changes, Glamsterdam introduces vital adjustments to gas pricing and state growth mechanics. Recognizing that the cost of expanding Ethereum’s global state is a primary driver of long-chain bloat, EIP-8037 increases and separately meters the financial and computational cost of creating new state. This is paired with EIP-8038, which updates general state-access costs across the virtual machine. Further adjustments target intrinsic transaction gas consumption, calldata processing, access lists, and overall block gas accounting.
Application developers and smart contract engineers are advised to proactively test their existing contracts and gas estimation logic against these revised rules. DApps that rely heavily on fixed gas stipends, hardcoded gas limits, or narrow assumptions regarding remaining execution gas may experience unexpected failures and will likely require code modifications. The Ethereum community has made available specific repricing impact guides and testing documentation to help developers identify vulnerable contracts and update their systems safely.
Beyond these major changes, the Glamsterdam specification incorporates a broad array of developer and validator-centric enhancements. These include the introduction of native ETH transfer logs, a dedicated slot-number opcode, an increased maximum contract size limit, a deterministic factory contract, and fresh stack-manipulation instructions designed to streamline smart contract development. On the consensus side, improvements feature forward-compatible data structures, technical mechanisms to exclude slashed validators from proposing future blocks, and increased maximum limits for validator exit and consolidation churn to improve network fluidity.
Security remains a paramount focus as the testnet activation approaches, with the Ethereum Bug Bounty Program officially active for all Glamsterdam specifications and associated EIPs. Independent security researchers and developers examining the proposed changes can review client implementations as soon as their corresponding releases are published and verified. The bounty program provides structured reward multipliers and guidelines for reporting vulnerabilities responsibly prior to mainnet rollout.
As the network points toward the October activation on Sepolia, the broader ecosystem is reminded that network upgrades require explicit, coordinated opt-in from the community. Non-staking node operators, solo stakers, and infrastructure providers on Sepolia must complete their client updates prior to the designated epoch and slot. For mainnet users and ordinary ETH holders, no immediate action is required at this stage, as the current announcement is strictly focused on testnet deployment. Once Sepolia activation is successfully achieved and monitored, subsequent discussions and announcements will pave the way for bringing Glamsterdam to Hoodi and eventually the Ethereum mainnet.
Ethereum & Smart Contracts
Ethereum & Smart Contracts
Ethereum & Smart Contracts
