The code does not lie; only the founders do.
On August 13, 2025, Justin Drake, Ethereum Foundation’s core researcher, stood in front of a screen and declared the end of an era. After eight years of funding SNARK-friendly hash research, the foundation is abandoning Poseidon. The reason? A cold, brutal calculation: minimal assumptions over performance. The move is not a bug fix. It is a paradigm shift—from “design hashes for SNARKs” to “design SNARKs for hashes.” The rug was pulled before the mint even finished, and the market hasn’t noticed.
Context: The Eight-Year Investment
Since 2018, the Ethereum Foundation has poured millions into SNARK-friendly hash research. The goal was simple: reduce the number of constraints in zero-knowledge proofs. Poseidon emerged as the winner—a hash function with algebraic structures that fit neatly into large prime fields. It powered ZK-Rollups, validator proofs, and privacy protocols. The ecosystem built around it: hardware accelerators, circuit libraries, and a generation of ZK developers trained in its use.
But the foundation also funded the alternative. In 2023, Benjamin Diamond and Jim Posen published Binius, a binary-field-based proof system. It was an academic curiosity—until it wasn’t. The key insight: binary fields map naturally to the bit-level operations of standard hashes like SHA256 and BLAKE2s. The cost of proving a standard hash in a SNARK dropped by orders of magnitude. Suddenly, Poseidon’s advantage was no longer a requirement. It was a trade-off.
Drake’s announcement codified this shift. The new roadmap: leanVM in 2027, full deployment by 2028. The core layer of Ethereum will use standard hashes, proven in binary-field SNARKs. The “minimal assumptions” philosophy—use only widely analyzed, time-tested cryptographic primitives—has won. The message is clear: we don’t trust the new stuff; we trust the gas fees.
Core: The Systematic Teardown
Let me be precise. I have audited ZK circuits for over six years. I have seen the damage caused by over-optimized hash functions that lack mature cryptanalysis. Poseidon is not broken. But it is a liability. Its algebraic simplicity, while efficient in SNARKs, makes it vulnerable to future attacks—especially from AI-driven cryptanalysis. Drake hinted at this: “More blood is coming” in the NIST post-quantum standardization process, where lattice-based HAWK and isogeny-based SQIsign were already compromised.
The shift to standard hashes is not about today’s security. It is about the next ten years. SHA256 and BLAKE2s have survived decades of scrutiny. Even under Grover’s algorithm, 256-bit outputs provide 128-bit quantum security—acceptable for most applications. Poseidon? Its mathematical structure is too clean. A significant algebraic attack could collapse decades of ZK infrastructure.
The performance reality: Drake claims a laptop can run ~1 million hash calls per second, only 100x slower than native CPU. That is within the same order of magnitude as Poseidon-based SNARKs. But “same order of magnitude” is not “identical.” In production, every extra millisecond of proof generation compounds across thousands of transactions. The true cost will only be known when leanVM ships in 2027.
The ecosystem disruption: Over 80% of ZK-Rollups today use Poseidon or similar SNARK-friendly hashes. The foundation’s message—“existing projects are not forced to migrate”—is technically correct but economically naive. The network effects will shift. Hardware accelerators for Poseidon will lose value. New tooling will target binary fields. Interoperability with Ethereum’s core layer will degrade. The voluntary migration will become a mandatory one, silently, over the next three years.
Reentrancy is not a bug; it is a feature of trust. The same logic applies here. The foundation is betting that the trust in standard hashes outweighs the efficiency gains of Poseidon. But trust is a double-edged sword. If a new attack on SHA256 emerges—however unlikely—the entire Ethereum security model would be compromised. The foundation is swapping one set of assumptions for another, betting that the older set is more robust.
Contrarian: What the Bulls Got Right
Let me give credit where it is due. The decision is not a FUD-driven panic. It is a calculated, long-term move. The bulls are right that this strengthens Ethereum’s narrative as a “trustworthy infrastructure” for institutional adoption. Regulators and nation-states will look more favorably on a blockchain that uses NIST-standardized hashes over proprietary ones. The minimal-assumptions approach aligns with the ethos of conservative security—a rare trait in crypto.
Furthermore, the timeline is reasonable. Three years from research to deployment is aggressive but not reckless. The foundation has the resources to fund the necessary development. And the shift positions Ethereum as a leader in post-quantum cryptography, which could become a major competitive advantage by 2030.
But the bulls underestimate the hidden costs. The eight-year investment in Poseidon is not a sunk cost; it is a lock-in. The developers, the hardware, the proofs—all of it will need to transition. The foundation’s declaration that “Poseidon is not obsolete” is a polite fiction. Once the core layer adopts standard hashes, the gravitational pull will be irresistible. Projects that delay migration will find themselves isolated, unable to cheaply prove transactions on Ethereum’s future proof system.
The rug was pulled before the mint even finished. The announcement itself is the trigger. The market has not priced in the three-year transition risk. The narrative is still “Ethereum is getting more secure,” but the reality is that a massive amount of technical debt is being created. The foundation is betting that the long-term payoff justifies the short-term friction. I am not convinced.
Takeaway: The Accountability Call
This is a generational bet. Ethereum is choosing to be the slow, secure, boring settlement layer—not the fast, experimental innovation hub. That is a defensible strategy. But the execution risk is high. The binary-field SNARK systems (Binius, Flock) are still academic. The leanVM design is a draft. The hardening process will reveal flaws that no audit can predict.
I don’t trust the audit; I trust the gas fees. The true test will come in 2027, when leanVM hits mainnet. Until then, treat this as a research direction, not a done deal. The code does not lie, but the roadmap does. And the roadmap is a promise, not a proof.
Watch the commit logs. Watch the EIP discussions. The real story is not in the announcement—it is in the implementation. And if the implementation stumbles, the rug will be pulled for real.
