Rebranding Lean Ethereum

Plus: ACDC #182 call summary and the dissolution of the EF Protocol Support team 🌙

Jul 10, 2026

Good evening,

Tonight, I’m discussing the status of the lean Ethereum project in light of the Ethereum Foundation Protocol team's updated strawmap proposal.

On Glamsterdam development, there are no major updates in tonight’s newsletter. For the latest ACD call summary, refer to the linked call notes at the bottom of the newsletter.

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Let’s get into it.

Yours truly,

Christine D. Kim

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Protocol Watch

The shot 🥛

The chaser 🍪

On Saturday, July 4, Vitalik Buterin, co-founder of Ethereum and a board member of the Ethereum Foundation (EF), shared an updated version of the strawmap.

The strawmap is a loose development roadmap outlining the major upgrades Foundation developers envision for Ethereum over the next three to four years. It was initially unveiled by the EF Protocol team in February and recently updated after an in-person gathering of Ethereum researchers in Berlin.

Compared to the one from February, the latest version of the strawmap:

Consensus layer (CL): Schedules a change to issuance between 2027 and 2028 in the I-star hard fork that was not there before
Data availability (DA): Pushes back blob capacity increases and other blob-related features, such as blob streaming, so that they occur later in the roadmap than before
Execution layer (EL): Fewer thinking face emojis, which illustrate greater certainty and consensus among Ethereum researchers on the EL-focused upgrades that will take precedence over the next three to four years

Overall, the strawmap appears simpler, more organized, and more concrete than the one from February. The new strawmap also prioritizes improvements to Ethereum Layer-1 over Ethereum’s Layer-2 ecosystem, which tracks with Buterin’s earlier posts about pivoting away from the rollup-centric roadmap.

However, as a reminder, the strawmap, as with any multi-year roadmap released by the EF, is subject to change and ongoing iteration. As stated on the strawmap website:

An “official” roadmap reflecting all Ethereum stakeholders is effectively impossible. Rough consensus is fundamentally an emergent, continuous, and inherent uncertain process.

All priorities and upgrades featured in the strawmap, except those explicitly labeled as “SFI” for the Glamsterdam upgrade, still require approval through the Ethereum governance process. This includes changes like EL headliners like FRAME and, of course, CL features like snail issuance.

The strawmap is a document created and maintained by one “node,” to use Buterin’s language, among many nodes that influence which features actually get built and implemented in the Ethereum protocol.

In prior years, the Foundation’s say in Ethereum’s research and development was the main source of truth and authority. However, due to its recent downsizing and restructuring, there is a greater likelihood that the EF Protocol’s view of Ethereum’s roadmap may no longer be the only view that matters to Ethereum’s development, and the opinions of other stakeholders, such as the newly founded EthLabs, could present views that oppose or change elements of the strawmap moving forward.

Redefining ‘lean Ethereum’

Aside from changes to the strawmap itself, Buterin’s comments on the updated strawmap, shared on X, were notable for affirming certain changes to the development of lean Ethereum.

As background, in 2024, EF Researcher Justin Drake unveiled the Beam Chain at Devcon, a biannual Ethereum conference organized by the EF. Drake described the Beam Chain as the next iteration of Ethereum’s CL, also called the Beacon Chain.

It would be quantum-secure with faster blocks and native zero-knowledge virtual machines (zkVMs). Drake said the specifications for the Beam Chain are already being worked on by multiple independent teams of developers.

Due to trademark issues with the name “beam,” the beam chain was later rebranded to “lean Ethereum.” Recurring calls were created on the Ethereum protocol meetings calendar to coordinate research and development for the lean project.

Over the last few years, work on lean has become sprawling, encompassing several parallel initiatives related to Ethereum’s quantum migration, fast finality, and zkVMs. Despite fanfare about lean specifications and client implementations already being tested on devnets, the work remains highly exploratory and experimental.

It is becoming less of a major upgrade to Ethereum and more of a catch-all phrase that references all the strawmap's north-star goals.

Buterin acknowledged this shift as one of the most important takeaways from the updated strawmap. Buterin said:

"Lean Ethereum" is not a single one-shot upgrade, it is a collection of improvements that will come online to the Ethereum network over the course of three or four years. But make no mistake, this IS the third major iteration of Ethereum in the same way that the Merge was the second. Almost every major piece of the protocol will be replaced …

Rather than lean Ethereum replacing the Beacon Chain, the research for lean Ethereum, which is really research into fast finality, quantum-resistance, and long-term Layer-1 scaling, will be merged piecemeal into the existing Beacon Chain.

This has wide-ranging implications for the lean consensus layer clients such as Ream, Zeam, and Qlean. They will likely no longer be designed as standalone clients to replace existing CL clients as originally thought. Their work, if any of it proves useful, will likely be folded into existing CL clients like Lighthouse and Prysm.

Further, it’s clear now that lean Ethereum is no longer pointing towards a standalone upgrade. It is looking ahead to several upgrades that together aim to make Ethereum a more performant protocol, leaving no aspect of the codebase untouched.

Finally, because lean Ethereum no longer represents a clean departure from existing Ethereum specifications, it is more likely to add to, rather than reduce, the protocol’s technical debt and complexity.

When first unveiling the idea for lean, then called beam, in 2024, Drake said on stage at Devcon:

With the benefit of hindsight, we now know what the mistakes we made with the Beacon Chain are, and we have a bunch of technical debt that is extremely sticky and tends to pile on over time and maybe now we have an opportunity to clear this technical debt.

As a project now envisioned to add more features to Ethereum piecemeal rather than overhaul several aspects of it with a single large upgrade, lean Ethereum is likely to increase the protocol’s technical debt over time before it ever reduces debt. One of the final pieces of the strawmap scheduled for 2029 and beyond is summarized on a card titled “tech debt reset”.

As with the initial ideation of the Merge upgrade, developers envisioned it as a clean migration to a new protocol. However, to minimize disruptions to applications and ensure backward compatibility, they ultimately decided to merge new code into the old. Developers are converging again on a similar plan with lean Ethereum: Add first, subtract later.

Bottom line

The new strawmap features minor changes and cleanups to the outlook for Ethereum development over the next three to four years. It is important to note that the strawmap is still subject to more change and iteration, especially as governance for the Hegota and other forthcoming forks proceeds.

The most important takeaway from the updated strawmap is Buterin’s remarks on what they mean for lean Ethereum.

As Buterin remarked, lean Ethereum is not a one-shot upgrade to the CL. It is a series of several upgrades that will leave no stone unturned in the protocol. Thus, lean Ethereum as the actualization of the strawmap is unlikely to reduce tech debt or ossify parts of Ethereum, as originally anticipated. Instead, it may add to the protocol’s burgeoning complexity, making each iterative upgrade more difficult and riskier to pursue.

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