Goodbye, Poseidon! An epic 8-year, 8-figure rabbit hole in post-quantum cryptography reaches its dream conclusion. The Ethereum Foundation is abandoning Poseidon for L1, pivoting to SHA or BLAKE. This milestone unlocks ultimate security for lean Ethereum and foreshadows a golden era of hash-based cryptography. Since 2018, the Ethereum Foundation has invested in magic cryptographic bricks, so-called "SNARK-friendly hashes". In 2019, Poseidon was born. It held strong and became the dominant SNARK-friendly hash, securing billions via zkrollups and zkVMs. In a stunning reversal, breakthrough SNARK designs show that SNARK-friendly hashes aren't necessary after all. Off-the-shelf traditional hash functions like SHA2 and BLAKE2s can now match Poseidon in a SNARK. In hindsight the key was not SNARK-friendly hashes, but hash-friendly SNARKs. The secret is doing maths over the smallest prime number: 2. So-called "binary fields" natively speak the language of bits, aligning with the boolean operations inside traditional hashes. This is a stark departure from "prime fields", where awkward large-prime arithmetic makes bit manipulation painfully expensive. We're talking sci-fi cryptography. 1M traditional hash calls proven per second, on a laptop. Just 100x overhead vs native CPU boolean compute. Nobody predicted such performance, not even the handful of binary-field visionaries. Hat tip to the research geniuses: Jim and Ben with Binius in 2023; Ron, Benedikt and William with Flock in June. With SHA2, the lean aesthetic of minimal assumptions reaches its climax. The EF's principled stance on pure hash-based cryptography has aged like fine wine. We now enjoy foundations the world can trust for decades and centuries, foundations worthy of the dream of an internet of value. Speed of deployment is a secondary win. There's no longer a need to wait years for Poseidon cryptanalysis to bake. Emile and Thomas from the EF post-quantum team are moving at breakneck speed with binary fields. The strawmap now points to a production-grade leanVM in 2027, with CL, DL, EL deployments in 2028. As AI becomes exceptional at cryptanalysis, the contrarian bet to avoid riskier structures like lattices and isogenies is visibly paying off. The past weeks have been brutal. Lattice-based "HAWK" and isogeny-based "SQIsign", both signature schemes in NIST's Round 3, have suffered blows. Sources I trust say more blood is coming. On AI, the open autoresearch trend kicked off by ECDSA[.]fail is spreading fast, with amazing outcomes from zk[.]golf and SNARK[.]fast. Days ago SNARK[.]fast crossed 1.8M BLAKE3/sec proven on an M3 Max. Stay tuned for fresh autoresearch challenges dropping tomorrow. Also tomorrow: Ethproofs call #10#, dedicated to binary fields. Possibly the most noteworthy Ethproofs call yet. Experts leading the charge will present the future of hash-based SNARKs at 2pm UTC. What an incredible time to be alive. To witness history, DM me for a calendar invite :) Today I can confidently claim that hash-based cryptography has won out for blockchain post-quantum signatures. SNARK succinctness compresses arbitrarily many signatures into one small proof per block. SNARK flexibility yields k-of-n threshold signatures, complex multisigs, and more. Ultimate security. Uncompromising performance. Full programmability. Believe in something. Believe in hashes.

Adding ZK to @Arbitrum BoLD protocol was surprisingly simple. How does it work? Today, BoLD settlement works like this: → Proposers can make assertions (a claim about the chain's new state); when a new assertion comes in a challenge timer starts → No rival assertion within the challenge window? The assertion is confirmed → Rival posted? The challenge protocol kicks in New multi-prover path (everything above still holds, plus): → A proposer can prove any unconfirmed assertion with a ZK proof + K-of-N attestations from the Fast Confirmation Committee → ZK proof verifies on the parent chain & enough attestations check out? The assertion settles early - no waiting out the challenge window Why this beats a ZK-only design: 1. Multi-prover security: Fast confirmation needs two independent systems to agree: a ZK proof verified on the parent chain + attestations from committee nodes re-executing the chain. To fast-confirm a bad state, an attacker has to break both at once. TEE-run committee nodes are planned as a further hardening step. 2. Deterministic upper bound on settlement: If the prover stalls or has a bug, the chain simply falls back to optimistic settlement: slower, never halted, funds untouched. A ZK-only chain in the same spot may never settle without security council action. 3. Pay for proving only when you need it: Proving is optional per assertion: pure fraud-proof chains pay nothing, Hybrid ZK chains proves on demand to settle early or resolve disputes, and ZK Prove All chains prove everything for always-fast settlement. ZK-only stacks have one mode: prove every batch, forever. @Offchain will bring a proposal to the DAO to upgrade Arbitrum One to ZK settlement, and other chains built with Arbitrum Platform will be able to upgrade at will. Stay tuned for more 👀

After 5+ years, we're winding down POAP. Over the years, we: * minted millions of collectibles across hundreds of communities. * did incredible collaborations with world-class organizations - Coinbase, Amex, WMG, Bayer, and a long tail of others, including countless in crypto. * ran one of the biggest activations at Devcon, minting 8000+ collectibles over the course of a week. * built an Airport Rally to let collectors get POAPs at airports around the world. POAP meant something to a lot of people. Unfortunately, crypto's funding cycles and distribution dynamics made it hard to build a sustainable company without cannibalizing the ethos that made POAP mean something. Building on a fragile and quickly evolving stack, in the middle of an incredible hype cycle, only added to the challenges. Still, there are some big lessons I am carrying from the POAP story. First: Customer communities are the most undervalued asset a company can have. If you build something with soul, people who use it and love it will take your brand everywhere. Do not underestimate the power of customer communities. Second: Connection is still the point. It's easy to lose that thread when the conversation is about the latest bubbly tech or price speculation, but the people using POAPs at events, in classrooms, at hackathons were getting something real out of it. Third: Longevity and brand equity are the only moats left. With the time to building and shipping something new collapsing quickly, and distribution becoming increasingly an engineering problem, customers increasingly want to make sure they can trust that the things they are buying will grow and evolve with the market, without changing radically. Grateful for everyone who believed in what we were building. It's too soon for me to say what's next, but for now, I'm thinking a lot about what GTM looks like in the age of AI.