# Lean / PQ Consensus — Social & Education Strategy

**December 2025**

## Goal

Create a shared, updated mental model of **Lean consensus = Post-Quantum Ethereum consensus**, and provide clear on-ramps for:

1. EF leadership & track leads
2. The broader EF
3. CoreDevs / ACD
4. Existing CL client teams

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## I. High-Level Strategy (HL)

### A. Align with Key Internal Stakeholders (EF leadership, track leads)

**1. Narrow and stabilize the framing**

* Lean consensus = **post-quantum hardening of Ethereum consensus**:
* PQ signatures
* PQ aggregation
* Snarkified / provable consensus
* PQ devnets and interop
* Explicitly de-scope:
* FOCIL → normal fork work, not Lean (this jumped out at Marius as still included)
* “Parallel chain” or “second Merge” narratives

**2. Explicitly update the Beam Chain mental model**

* Acknowledge evolution since the original Beam Chain talk:
* Less about replacing clients or bundling everything
* More about PQ readiness + long-term consensus security
* Encourage Justin to clearly articulate:
* *What changed*
* *What is no longer in scope*
* *What is still exploratory vs committed*

**3. Anchor Lean/PQ in shared goals**

* Reiterate consistently:
* Same end goal as everyone else (secure, decentralized, scalable settlement)
* Disagreements are about **path and packaging**, not objectives
* Position Lean as **complementary** to existing roadmaps, not competing.

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### B. Socialize Across the Entire EF

**4. Clarify what Lean is (and is not)**

* There is:
* No second long-running chain
* No forced client reset
* No immediate fork commitment
* Lean is best understood as:
* A **bundle of long-term EIPs and research tracks**
* A backstop and proving ground for future consensus upgrades

**5. Be transparent about cryptography maturity**

* Communicate clearly:
* PQ signature scheme: high confidence (~90%)
* Aggregation: experimental, multiple designs in flight
* Hash- vs lattice-based: still open
* Emphasize modularity:
* Validators rotate keys once
* Aggregation can evolve independently

**6. Align internally before external amplification**

* Reduce drift between:
* Public messaging (pods, talks)
* Internal EF understanding
* Use “glue” roles (track leads, coordinators) to keep:
* CL, EL, cryptography, ZK-EVM, and PQ teams in the same loop
* Marius offered to serve in this capacity

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### C. Socialize with CoreDevs & the Wider Ethereum Ecosystem

**7. Repeatedly reinforce the core value proposition**

* Lean/PQ addresses **inevitable problems**:
* Post-quantum security
* Long-term consensus provability

**8. Use CoreDev-appropriate channels**

* Short-form first:
* “Lean consensus: 2025 update — what it is / isn’t”
* Long-form follow-up:
* “Lean Chain, one year later”
* Synchronous:
* ACD update slot once Glamsterdam scoping pressure eases
* Invite CoreDevs to attend PQ update calls

**9. Clarify deployment philosophy**

* Lean is:
* A **direction and toolkit**, not all-or-nothing
* Messaging to CoreDevs:
* Some components (e.g. fast finality variants) may ship incrementally
* Lean serves as a backstop if incremental paths become too invasive or blocked

**10. Use key moments intentionally**

* EF town hall (early Feb): internal clarity
* All-CL discussion (late Feb): expectations + capacity
* EthCC / Cannes workshop (March):
* One “scout” per CL team
* Concrete walkthroughs (PQ, finality, LeanVM)
* Case studies (e.g. Lighthouse fork)
* Structured feedback on rollout paths
* Justin might want to consider capping this off with an EthCC Keynote so that the updated messaging of what Lean Is starts to drown out the OG Beam Chain talk

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## II. Consensus-Layer–Specific Strategy (CL)

### A. Set Clear Expectations for CL Teams

**11. Acknowledge capacity constraints**

* Many teams are fully loaded just maintaining forks.
* Make explicit:
* Lean work does *not* preempt near-term fork work
* Early engagement can be minimal and scoped
* Funding only scales with rough consensus that Lean is critical-path

**12. Promote the “scout” model**

* Pattern:
* One engineer explores early
* Prototypes and learns
* Team engagement scales later if/when needed
* Ask:
* Each CL team to nominate a scout once timelines are clearer
* Emphasize:
* Early scouting is exploratory, not a commitment to ship

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### B. Make Lean Easier to Engage With (Developer Experience)

**13. Improve shared artifacts**

* Maintain a single source of truth:
* Devnet → spec commit mapping
* Invest in:
* Clear, high-level design docs
* Robust test vectors early (avoid byte-by-byte interop debugging)
* Tooling that makes Lean feel “push-button” over time

**14. Clarify client-ecosystem expectations**

* Acknowledge concerns about client proliferation.
* Communicate EF’s current stance:
* Lean funding so far is modest (~$1M / year)
* Several teams are self-funded
* No forced fragmentation
* Consolidation over time is possible and not taboo
* Major funding shifts only with CoreDev buy-in

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## Summary Message to Reiterate Everywhere

> **Lean consensus is Ethereum’s post-quantum path forward — a long-term security and provability project designed to integrate with existing clients, not replace them.**