Glamsterdam, Ethereum's third hard fork in twelve months, introduces on-chain block building and parallel transaction processing to cut gas fees by 78.6% and target 10,000 TPS.
Ethereum developers are targeting the first half of 2026 for Glamsterdam, the network's third hard fork in twelve months, introducing a suite of changes that could reduce transaction fees by as much as 78.6 percent and push throughput toward 10,000 transactions per second — roughly ten times Ethereum's current capacity. The upgrade's two headline proposals, EIP-7732 and EIP-7928, will respectively move block construction onto the protocol itself and enable parallel transaction processing for the first time in Ethereum's history.
The scale of the proposed changes marks a significant departure from Glamsterdam's immediate predecessors. Pectra, finalised in May 2025, focused on validator experience and blob throughput for Layer 2 networks. Fusaka, which shipped in December 2025, targeted data availability at the base layer. Glamsterdam turns the lens inward, addressing the mechanisms by which blocks are assembled and executed — inefficiencies that have persisted since Ethereum's proof-of-stake Merge in September 2022.
What follows is an examination of the technical architecture underpinning Glamsterdam, the concerns its design has raised among developers, and what the upgrade's timeline means for Ethereum's competitive position as Layer 1 throughput becomes an increasingly contested variable.
How EIP-7732 Moves Block Building On-Chain
The centrepiece of Glamsterdam is Enshrined Proposer-Builder Separation, or ePBS, codified in EIP-7732. Today, block construction on Ethereum relies on a trust relationship between block builders and off-chain relay networks — most prominently Flashbots — which act as intermediaries between builders assembling transactions and validators proposing blocks. ePBS replaces that voluntary arrangement with a cryptographically enforced, protocol-level system. Under the new design, builders submit sealed block bids; validators select the highest bid without examining transaction contents; and the block is revealed only after the commitment is locked in.
The on-chain audit trail this creates addresses one of the most persistent criticisms of the existing infrastructure: that maximal extractable value flows through opaque relay systems operating outside Ethereum's consensus rules. According to projections cited by developers, ePBS could reduce MEV extraction by up to 70 percent by creating rule-bound block production rather than the trust-dependent relay architecture that currently dominates. Tomasz Stańczak, former co-executive director of the Ethereum Foundation, described the change as converting what is presently a handshake agreement into 'an on-chain auction plus protocol-enforced execution.'
Despite the theoretical elegance of ePBS, academic modelling has raised nuanced concerns. Research cited in Ethereum developer discussions suggests that MEV incentives may migrate rather than disappear: while validator concentration is expected to fall, builder concentration could increase as the most sophisticated participants outcompete smaller builders in an on-chain auction environment. Separately, the 'free option problem' — where builders could in theory withhold blocks to exploit short-term price movements — is estimated to affect approximately 0.82 percent of blocks under normal conditions, rising toward 6 percent during periods of elevated volatility.
Parallel Processing and the Gas Repricing Overhaul
The second major component of Glamsterdam is EIP-7928, which introduces Block-Level Access Lists. Today, Ethereum processes transactions sequentially: each transaction is executed one after another, and the outcome of one may depend on state changes made by its predecessor. Access Lists require transaction senders to pre-declare which accounts and storage slots their transactions will interact with. This information is made available at the block level, allowing the network to identify non-conflicting transactions and process them simultaneously — an architectural shift analogous to moving from single-lane to multi-lane processing.
Combined with a package of gas repricing EIPs including EIP-7904, these changes are designed to raise the per-block gas limit from its current 60 million to 200 million — stepping first to 100 million during early deployment, then scaling further once ePBS is fully operational. According to Ethereum Foundation projections, this expansion combined with parallel execution would push the network's theoretical throughput toward 10,000 transactions per second. A separate repricing exercise decouples state creation costs from execution costs, addressing concerns that rising throughput would proportionally inflate Ethereum's state size.
The gas repricing measures are expected to benefit regular users disproportionately. According to developer documentation, fees for standard smart contract calls should fall approximately 78.6 percent, while costs for new state creation — relevant primarily to application developers deploying fresh contracts — may increase modestly. This asymmetry reflects a deliberate prioritisation of end-user accessibility over developer convenience in the upgrade's design.
Glamsterdam's Place in Ethereum's Twelve-Month Transformation
Glamsterdam will be the third Ethereum protocol upgrade to ship within a calendar year, a pace that would have been considered ambitious even by the standards of the network's early development. Its predecessors targeted distinct layers of the stack: Pectra enhanced the validator experience and increased blob capacity critical for Layer 2 networks such as Arbitrum and Optimism; Fusaka extended Ethereum's data availability layer, a prerequisite for the continued growth of rollup-based scaling. Glamsterdam addresses the final major structural bottleneck: the base layer's execution engine and block production mechanism.
Vitalik Buterin outlined the eight EIPs forming Glamsterdam's scope in a detailed post in late February 2026, framing the upgrade as a necessary foundation for subsequent enhancements rather than a standalone performance release. The Ethereum Foundation's DevOps team had completed validation on Devnet-4 by early April and was transitioning to Devnet-5, with public testnet deployment expected in spring ahead of dual audit phases. A tentative June 2026 mainnet date has been floated by developers, though they have emphasised it remains subject to testnet outcomes.
The historical comparison most frequently cited by Ethereum researchers is the Merge itself, executed in September 2022, which switched the network from proof-of-work to proof-of-stake consensus. While technically transformative, the Merge intentionally did not alter execution throughput — a deliberate design choice that left user fees unchanged and contributed to the subsequent proliferation of Layer 2 networks. Glamsterdam represents the first substantive attempt to address that legacy limitation at the base layer rather than through separate scaling solutions.
Developer Caution and Ethereum's Market Position
Despite broad consensus on the upgrade's goals, several development teams have flagged implementation risks. Engineers at Base, the Coinbase-backed Layer 2 network, warned in early 2026 that the inclusion of FOCIL — Fork Choice Forced Inclusion Lists, a censorship-resistance mechanism — could delay Glamsterdam's mainnet deployment beyond 2026. Ethereum developers subsequently agreed to defer FOCIL to the following upgrade, Hegotá, scheduled for the second half of 2026, in order to preserve the current timeline.
The cautious approach to FOCIL reflects a broader tension in Ethereum's development culture between shipping upgrades quickly and preserving the network's reputation for rigorous safety standards. ETH was trading near $2,040 as of April 5, 2026 — approximately 56 percent below its late-2025 high near $4,600. Analysts at multiple firms have noted that Layer 2 networks have progressively absorbed transaction activity from Ethereum mainnet, compressing fee revenue and softening ETH's price support, underscoring the urgency of demonstrating base-layer performance improvements.
What Comes Next: Hegotá and the Longer Roadmap
Glamsterdam is designed as a foundation for subsequent improvements rather than a complete solution. FOCIL, deferred to Hegotá, gives validators a final line of defence against builder censorship by allowing them to publish mandatory transaction inclusion lists. Without FOCIL, critics argue, ePBS could theoretically permit a dominant builder to selectively exclude certain transactions — a concern Ethereum developers acknowledge but consider manageable in the near term given the competitive builder market expected to emerge.
Vitalik Buterin has also outlined plans for encrypted mempools as a longer-term research direction, aimed at preventing front-running before transactions are included in blocks. These features, if implemented, would make the MEV mitigation introduced by Glamsterdam more comprehensive. For now, the network's focus remains on delivering ePBS and parallel processing on schedule, with developers emphasising that even a partial throughput increase would meaningfully lower costs for the estimated 50 million addresses that have interacted with Ethereum smart contracts in the past year.
The pace of protocol development, combined with the approaching public testnet phase, suggests that the June 2026 target remains achievable barring unforeseen complications. Whether Glamsterdam translates into renewed market confidence for ETH will depend as much on application-layer demand as on technical execution — a dynamic that will become clearer as testnet validation progresses through spring.
