Gloas for the consensus layer and Amsterdam for the execution layer come together to form Glamsterdam, Ethereum’s next major network upgrade, which has successfully passed its first primetime test.
Glamsterdam officially went live on the Sepolia testnet, with the blockchain successfully finalizing blocks through the cutover transition without experiencing any critical disruptions or hiccups. While this milestone remains confined to testnet activity for now, its implications are considerable for the original smart contract network, signaling a structural shift in how the leading layer-one blockchain will handle transactional throughput moving forward.
As Ethereum researchers and core developers have noted, the upgrade marks a pivotal opening for what could be the network’s largest throughput increase since its initial launch. The architectural changes embedded within Glamsterdam are built to accommodate a targeted gas limit of roughly 200 million, representing a roughly 3.3-fold jump from the 60 million limit currently utilized on the Ethereum mainnet. For historical context, the mainnet gas limit sat at 30 million for years before validators incrementally raised it to 60 million across three separate adjustments. Even the London upgrade’s historic doubling of the maximum block size back in 2021 kept the active gas target at 15 million.
Despite the ambitious numbers, the fork itself will not automatically flip a switch to instantly make Ethereum blocks three times larger the moment it activates. Instead, the upgrade fundamentally alters the mechanics of how blocks are produced and validated, creating a safer technical environment for much larger blocks to be generated. Once deployed, individual validators will retain the autonomy to decide whether and when to raise the network gas limit.
Glamsterdam’s Core Architecture and Technical Vision
The upcoming hard fork bundles 18 Ethereum Improvement Proposals (EIPs) in total, but three primary technical proposals are engineered to do the heavy lifting required to safely scale the network’s capacity.
The first major pillar is enshrined proposer-builder separation, widely known as ePBS. To simplify the intricate mechanics, this mechanism is designed to grant Ethereum validators substantially more time to process network data. Under the current operational model, most Ethereum blocks are constructed by specialized external builders and subsequently passed along to validators through trusted intermediary entities called relays. With the implementation of EIP-7732, the block proposer will instead commit to a cryptographically signed bid provided by a builder, allowing the builder to reveal the full contents of the block afterward.
This decoupling means that the intensive computational task of checking a block’s transactions no longer needs to be frantically crammed into the brief four-second attestation window. According to the specifications of the EIP, most validators will henceforth be afforded roughly nine seconds to complete their validation duties.
The second significant pillar arriving with Glamsterdam is the introduction of block-level access lists, or BALs. These lists establish a novel capacity for parallel transaction processing on the network. Under the existing framework, Ethereum execution clients typically process a block’s transactions sequentially, inspecting them one by one because they cannot know in advance which specific state variables each transaction will touch.
EIP-7928 changes this paradigm by making every network block ship with an explicit map detailing all state variables it touches, alongside the subsequent values they will produce. Armed with this architectural guide, client software can efficiently prefetch required data and validate multiple transactions in parallel. To use an industrial analogy, ePBS is akin to giving quality control inspectors more time for comprehensive reviews, while BALs provide the factory floor with all necessary resources so that several assembly lines can operate simultaneously.
Additionally, the upgrade introduces larger contract sizes alongside a careful structural repricing of network resources. EIP-7954 is set to raise the maximum smart contract size from 24 KiB to 64 KiB, easing a restrictive bottleneck that has historically forced complex decentralized applications to split their underlying code across multiple separate contracts.
Concurrently, the fork will increase the cost of creating scarce network state. Under EIP-8037, the gas cost required to initialize a fresh storage slot will jump significantly from 20,000 to 97,920 gas, while a standard plain ETH transfer directed to an existing account will remain capped at 21,000 gas pursuant to EIP-2780.
Analyzing the Sepolia Deployment and the Road to Mainnet
The Sepolia testnet’s first Glamsterdam block landed with a 60 million gas limit, matching the operational cap currently utilized on the Ethereum mainnet. Following the initial activation, Sepolia’s gas limit scaled up to the targeted 200 million mark roughly 11 hours after the fork and has successfully maintained that threshold since.
Because each individual block proposer is structurally restricted from nudging the gas limit by more than roughly 0.1 percent per block, theoretical calculations suggest that if every single proposer had aggressively raised the limit on every sequential block, Sepolia could have completed the transition in approximately four hours. In practice, the ramp-up took more than twice that duration. Core developers attribute this delay partly to the fact that two popular consensus clients, Prysm and Teku, kept their respective validators operating at the 60 million cap post-fork unless node operators explicitly opted in to the higher 200 million limit.
Early performance telemetry shared by core researchers suggests that the technical levers introduced by the upgrade are already delivering tangible efficiency gains. Initial metrics indicate that client software handles individual units of gas noticeably faster than before the fork. For instance, executing a 40 million gas block that previously required Go Ethereum roughly 115 milliseconds to process now takes approximately 30 milliseconds under the new architecture. While these observations are drawn from preliminary data captured from a single node per client during the initial operational window, they provide a highly encouraging foundation for the upgrade.
Looking ahead, with the Sepolia testnet deployment successfully completed, attention turns toward the Hoodi testnet, which is slated to undergo the Glamsterdam deployment next. October 27th has been tentatively discussed as a target date for this upcoming activation, though scheduling remains fluid. Meanwhile, the core developer consensus continues to target the Ethereum mainnet for deployment at some point during the fourth quarter of 2026.
Observers note that development timelines have previously shifted. Glamsterdam was originally penciled in for the first half of 2026, and Sepolia’s specific testnet fork slipped from August 3rd to October 6th. Consequently, further timeline adjustments remain a distinct possibility as rigorous testing continues across additional public test environments.
Broader Ecosystem Implications and Scaling Potential
The introduction of Glamsterdam will naturally introduce new operational dynamics and technical considerations for developers, node operators, and infrastructure providers across the ecosystem.
Certain third-party Ethereum tooling will require updates to remain compatible with the architectural changes introduced by the upgrade. The Ethereum Foundation has previously issued warnings to developers of wallets, block indexers, and gas estimation utilities that rely on assumptions of a rigid, static maximum gas limit, noting that these applications must be updated to prevent disruptions.
Furthermore, the strategic repricing surrounding new state creation means that on-chain activities involving the generation of numerous new accounts or storage allocations—such as token airdrops, high-volume NFT mints, and wallet initialization campaigns—will incur higher costs, while everyday peer-to-peer transfers remain unaffected.
Ultimately, these intricate adjustments represent minor friction points when weighed against the broader structural impact of the upgrade. The primary narrative centers on the reality that the Ethereum layer-one environment is expanding its physical capacity, offering a more accommodating foundation for both traditional financial experiments and novel decentralized applications alike. By providing a wider margin for peak usage periods, the network can absorb sudden surges in demand without pricing out everyday participants, securing additional room for future ecosystem growth.
Tokenomics & Digital Assets
Tokenomics & Digital Assets
Tokenomics & Digital Assets
