Ethereum's Fusaka Upgrade Targets 16x Data Capacity by November 2025, Paving Way for Censorship-Resistant Glamsterdam

Ethereum core developer Preston Van Loon recently joined Bankless to discuss the network's ambitious roadmap, highlighting the upcoming Fusaka and Glamsterdam hard forks. The conversation, shared via a Bankless tweet, centered on how these upgrades aim to significantly enhance Ethereum's scalability, efficiency, and censorship resistance. Fusaka is slated for late 2025, with Glamsterdam following in 2026.

The Fusaka upgrade, expected to activate in November 2025, is poised to be a major step in Ethereum's "Surge" phase. A central component is the PeerDAS (Peer Data Availability Sampling) upgrade, detailed in EIP-7594. According to the Bankless tweet:

"Fusaka’s PeerDAS upgrade could 16x Ethereum’s data capacity without increasing validator storage, unlocking cheaper and faster Layer 2s." This mechanism allows validators to sample portions of data blobs rather than downloading full datasets, easing node burdens and boosting rollup performance.

Fusaka bundles 11 Ethereum Improvement Proposals (EIPs) focused on backend improvements, node resilience, and efficiency. Beyond PeerDAS, the upgrade includes EIP-7825 for spam resistance and EIP-7935, which proposes an increase in the default block gas limit, potentially scaling towards 150 million units. These changes are designed to improve overall network throughput and stability without altering existing smart contracts. Development for Fusaka has progressed through Devnet-3 in July 2025, with public testnets scheduled for September and October, leading to its mainnet activation.

Looking ahead to 2026, the Glamsterdam upgrade is set to build upon Fusaka's foundations, focusing on strengthening Ethereum's core values of decentralization and censorship resistance. Key proposals under consideration include Enshrined Proposer-Builder Separation (ePBS) and Fork-Choice Enforced Inclusion Lists (FOCIL), also known as Fossil. The Bankless tweet noted:

"Glamsterdam’s push for unstoppable settlement through EPBS and Fossil, enshrining proposer builder separation and strengthening censorship resistance."

ePBS (EIP-7732) seeks to integrate the builder role directly into the Ethereum protocol, reducing reliance on external, trusted relays and streamlining the block production flow. This separation is expected to enhance decentralization and improve block dissemination. Fossil (EIP-7805) aims to combat censorship by allowing a decentralized committee of attesters to force the inclusion of specific transactions into builder blocks, ensuring that transactions cannot be indefinitely excluded by a few large builders.

Preston Van Loon also provided insights on "shorter slot times, validator UX, and how community feedback shapes Ethereum’s roadmap," as stated in the tweet. The Ethereum ecosystem operates on an accelerated six-month upgrade cadence, demonstrating a continuous commitment to iterative improvements. These forthcoming upgrades underscore Ethereum's ongoing efforts to balance performance, decentralization, and user experience, preparing the network for broader adoption and increased demand.