Layla Zulfa
Ethereum’s core development continues at an accelerating pace, with the highly anticipated Fusaka upgrade poised for activation on December 3rd, 2025. This significant milestone comes as the network’s developers simultaneously ramp up planning for the subsequent Glamsterdam upgrade, targeting a release sometime in 2026, and begin preliminary discussions for the Heka / Bogotá upgrade. The rapid succession of these hard forks underscores the Ethereum community’s commitment to continuous improvement, scalability, and decentralization, even as it navigates complex decisions regarding feature prioritization and development timelines.
The "Checkpoint" series serves as a crucial high-level digest of these intense development cycles, providing periodic updates every 4-6 weeks to keep the broader community informed. Complementing this, the Forkcast platform has emerged as an invaluable resource, offering near real-time summaries, chat logs, and full transcripts of the weekly All Core Developer (ACD) calls, ensuring transparency and accessibility for all interested parties.
Fusaka: A Smooth Sail to Mainnet Deployment
The Fusaka upgrade, detailed under Ethereum Improvement Proposal (EIP) 7607, is on the cusp of mainnet activation. Scheduled for December 3rd, 2025, at 21:49 UTC, this upgrade marks a pivotal moment, having undergone an exceptionally smooth testing phase. All three major testnets successfully integrated Fusaka and its accompanying BPO forks (EIP-7892) with minimal complications, a notable achievement compared to previous Ethereum upgrades. This seamless transition through testing environments has instilled confidence among core developers, signaling a robust and well-prepared deployment.
The BPO forks, specifically EIP-7892, are designed to incrementally increase the network’s data availability capacity, a critical step in supporting Ethereum’s rollup-centric roadmap. The first BPO fork is slated for December 9th, 2025, at 14:21 UTC, increasing the target blobs to 10 and max blobs to 15. The second, more substantial BPO fork will activate on January 7th, 2026, at 01:01 UTC, further expanding capacity to 14 target blobs and 21 max blobs. These phased increases are vital for enhancing the efficiency and cost-effectiveness of Layer 2 solutions that rely on Ethereum for data availability.
Node operators play a critical role in ensuring the network’s continued functionality post-upgrade. It is imperative that all operators update their client software before the December 3rd deadline to maintain compatibility with the upgraded network. Fortunately, the client releases prepared for Fusaka contain configurations for all three upcoming forks, streamlining the update process to a single action. To celebrate this significant event and ensure widespread awareness, the Ethereum Protocol YouTube channel will host a live watch party during the Fusaka activation.
Gas Limit Expansion: Boosting Network Throughput
Concurrent with the Fusaka deployment, the Ethereum network’s default gas limit will be increased to 60 million. This adjustment is a testament to the collaborative efforts of client teams, all of whom have confirmed their readiness for this higher capacity. The increase is not merely a one-off event but part of a strategic, ongoing effort to enhance network throughput. Nethermind has spearheaded the development of a structured framework for safely determining optimal gas limit increases, paving the way for continued regular adjustments. This proactive approach aims to provide more transaction capacity and reduce average transaction fees, benefiting all network users. While the default will be 60 million, individual node operators retain the flexibility to manually configure higher limits, signaling their support for further expansion, a process actively encouraged by initiatives like "Pump the Gas."
Glamsterdam Takes Center Stage: A New Era of Structured Development
With Fusaka’s successful rollout imminent, the development community’s focus is decisively shifting towards Glamsterdam, the next major network upgrade. Slated for "some time in 2026," Glamsterdam (EIP-7773) is poised to introduce transformative features, most notably Enshrined Proposer-Builder Separation (ePBS) and Block-level Access Lists (BALs). These "headliner" features were chosen in August 2025 after extensive deliberation, reflecting their foundational importance to Ethereum’s long-term vision.
ePBS is a crucial step towards mitigating Maximal Extractable Value (MEV) concerns and enhancing censorship resistance within the network. By separating the roles of block proposer and block builder, ePBS aims to create a more equitable and decentralized block production process. BALs, on the other hand, are designed to improve transaction inclusion fairness and potentially simplify block construction, reducing complexity for builders and enhancing network predictability.
Reforming the Upgrade Scoping Process
The planning for Glamsterdam marks a significant departure from previous upgrade cycles, particularly in response to lessons learned from the Pectra fork in 2024. Pectra, initially conceived without a clear headliner and with a flexible timeline, became overburdened with features, ultimately necessitating a split into two separate upgrades. This experience highlighted the need for a more disciplined and structured approach to network upgrades.
In response, Tim Beiko, the ACDE call facilitator, proposed a clearer, more stringent framework for scoping upgrades. Glamsterdam is the first upgrade to fully embrace this new methodology, featuring a defined timeline and explicit deadlines for feature proposals. This structured approach has led to an unprecedented volume of proposed features, with 48 "non-headlining" EIPs submitted by the October 30th deadline. Core developers and the broader community are now actively engaged in reviewing this extensive list, evaluating features based on urgency, compatibility, and complexity to determine which will be included in the final Glamsterdam scope. The Ethereum Magicians forum serves as the primary venue for community input, with calls for users of the core protocol to articulate the urgency of specific features, ensuring that user needs are adequately represented in the decision-making process.
The FOCIL Debate: Censorship Resistance in Focus
Among the hotly debated features for Glamsterdam is Fork-choice enforced Inclusion Lists (FOCIL), an anti-censorship mechanism that has garnered exceptionally strong community support. FOCIL aims to enhance the network’s resilience against transaction censorship by ensuring that valid transactions are eventually included in blocks, regardless of a block builder’s preferences.
Despite its robust backing, FOCIL was initially moved to a "Considered" status for Glamsterdam, conditional on the progression of ePBS and BALs, and crucially, on its implementation not significantly delaying the overall upgrade. More recently, discussions during the All Core Devs (ACD) calls have leaned towards delaying FOCIL’s inclusion to the subsequent Heka / Bogotá upgrade. This potential deferral is contingent on a "credible commitment" for its inclusion in that future upgrade, a measure designed to provide clarity for developers regarding their resource allocation and prevent FOCIL from remaining in an indefinite state of limbo.
The debate around FOCIL underscores a fundamental tension within Ethereum development: the balance between technical feasibility, development timelines, and the philosophical commitment to core values like censorship resistance. Delaying such a critical feature carries the risk of diminishing its perceived urgency over time, especially if other "shiny new major features" emerge. Maintaining active community support and ensuring a concrete commitment for FOCIL’s inclusion in Heka / Bogotá will be paramount to its eventual implementation, reinforcing Ethereum’s dedication to its decentralized ethos.
Heka / Bogotá: The Horizon Beyond Glamsterdam
As development progresses on current and near-future upgrades, the Ethereum community is already looking ahead to the Heka / Bogotá upgrade, expected to kick off discussions in early 2026. Heka has been selected as the star name for the consensus layer, while the portmanteau for the full upgrade name (combining Heka with Bogotá for the execution layer) is still under consideration. Following the recent ACD calls, FOCIL is widely expected to be a frontrunner for headliner status in Heka / Bogotá, provided sustained community advocacy.
This established cadence of planning one fork while implementing another is a direct result of the lessons learned from past overburdened upgrades. It aims to foster greater efficiency and predictability in the development roadmap, allowing developers to allocate resources more effectively.
The Devconnect Effect: In-Person Collaboration and Decision-Making
The timing of these discussions coincides with Devconnect week, a period that typically sees a slowdown in the usual weekly call cadence due to travel and in-person events. Indeed, the next two Monday Testing calls have been cancelled. However, Devconnect also presents a unique opportunity for accelerated decision-making. Face-to-face discussions among core developers, researchers, and client teams can often resolve complex technical and social coordination issues more rapidly than asynchronous online interactions. This intense period of in-person collaboration could prove decisive for finalizing Glamsterdam’s minor features and solidifying the roadmap for future upgrades.
Balancing Innovation with Stability: A Continuous Challenge
Ethereum’s development trajectory reflects a dynamic tension between the desire to "ship fast" and the imperative to "ship safe." The Fusaka upgrade, shipping approximately six months and 26 days after Pectra, exemplifies a leaning towards a faster deployment pace, with timelines sometimes determined by the readiness of most clients rather than all. While this approach can accelerate progress, it also requires careful risk management.
The success of the new structured process pioneered in Glamsterdam will be a critical indicator for future development cycles. If it leads to less chaos, reduced stress, and greater efficiency than the Pectra experience, it would underscore the value of long-term planning and clearly defined steps. This could then enable experiments with better parallelization of planning and development for subsequent forks, further accelerating Ethereum’s evolution. Conversely, if Glamsterdam still proves overwhelming, the community will need to revisit strategies for managing the sheer enthusiasm for adopting a wide array of features, ensuring that ambition is tempered with realistic scope management.
The ongoing evolution of Ethereum is a testament to its vibrant and dedicated community. From the immediate impact of Fusaka to the strategic planning for Glamsterdam and Heka / Bogotá, each step forward is a complex interplay of technical innovation, community consensus, and a steadfast commitment to building a more scalable, secure, and decentralized future. The transparency offered by platforms like Forkcast and the "Checkpoint" series ensures that this journey remains open and accessible to all who wish to participate in shaping the world’s leading smart contract platform.
