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Nico

@nmohnblatt.me.bsky.social

picious until proven otherwise. Cryptography research and auditing at zkSecurity. Recurring co-host on the ZKPodcast. nmohnblatt.me

300 Followers  |  165 Following  |  56 Posts  |  Joined: 12.04.2023  |  2.3735

Latest posts by nmohnblatt.me on Bluesky

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Accelerating Scientific Research with Gemini: Case Studies and Common Techniques Recent advances in large language models (LLMs) have opened new avenues for accelerating scientific research. While models are increasingly capable of assisting with routine tasks, their ability to co...

On using LLMs for research (beyond basic prompts). Section 3.2 is specifically about catching a bug in a recent SNARG paper

arxiv.org/abs/2602.03837

07.02.2026 23:05 โ€” ๐Ÿ‘ 1    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 1

Amazing work from Yoichi giving a Lean proof of my recent FRI security paper (w/ Albert Garreta and Benedikt Wagner)

Super interesting workflow as well, combining TeX-to-Lean models with regular coding agents. I think we'll see a lot more of this moving forward!

27.01.2026 09:44 โ€” ๐Ÿ‘ 3    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

I haven't had a look actually. But I suspect that's the only viable option for now

24.12.2025 15:03 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Confessions to a data lake Iโ€™ve been building Confer: end-to-end encryption for AI chats. With Confer, your conversations are encrypted so that nobody else can see them. Confer canโ€™t read them, train on them, or hand them over ...

Great short article from Moxie. Right in time for family dinners and questions about AI and privacy

confer.to/blog/2025/12...

24.12.2025 13:58 โ€” ๐Ÿ‘ 5    ๐Ÿ” 2    ๐Ÿ’ฌ 2    ๐Ÿ“Œ 0
Abstract. In outsourcing computation to untrusted servers, one can cryptographically ensure privacy using Fully Homomorphic Encryption (FHE) or ensure integrity using Verifiable Computation (VC) such as SNARK proofs. While each is practical for some applications in isolation, efficiently composing FHE and VC into Verifiable Computing on Encrypted Data (VCoED) remains an open problem.

We introduce Laminate, the first practical method for adding integrity to BGV-style FHE, thereby achieving VCoED. Our approach combines the blind interactive proof framework with a tailored variant of the GKR proof system that avoids committing to intermediate computation states. We further introduce variants employing transcript packing and folding techniques. The resulting encrypted proofs are concretely succinct: 270kB, compared to 1TB in prior work, to evaluate a batch of Bโ€„=โ€„2ยนโด instances of size nโ€„=โ€„2ยฒโฐ and depth dโ€„=โ€„32. Asymptotically, the proof size and verifier work is O(dlogโ€†(Bn)), compared to ฮฉ(BNlogโ€†n) in prior work (for ring dimension N).

Unlike prior schemes, Laminate utilizes the full SIMD capabilities of FHE for both the payload circuit evaluation and proof generation; adds only constant multiplicative depth on top of payload evaluation while performing Oฬƒ(n) FHE operations; eliminates the need for witness reduction; and is field-agnostic. The resulting cost of adding integrity to FHE, compared to assuming honest evaluation, is โ€„โˆผโ€„12ร— to โ€„โˆผโ€„36ร— overhead (for deep multiplication-heavy circuits of size 2ยฒโฐ), which is โ€„>โ€„500ร— faster than the state-of-the-art.

Abstract. In outsourcing computation to untrusted servers, one can cryptographically ensure privacy using Fully Homomorphic Encryption (FHE) or ensure integrity using Verifiable Computation (VC) such as SNARK proofs. While each is practical for some applications in isolation, efficiently composing FHE and VC into Verifiable Computing on Encrypted Data (VCoED) remains an open problem. We introduce Laminate, the first practical method for adding integrity to BGV-style FHE, thereby achieving VCoED. Our approach combines the blind interactive proof framework with a tailored variant of the GKR proof system that avoids committing to intermediate computation states. We further introduce variants employing transcript packing and folding techniques. The resulting encrypted proofs are concretely succinct: 270kB, compared to 1TB in prior work, to evaluate a batch of Bโ€„=โ€„2ยนโด instances of size nโ€„=โ€„2ยฒโฐ and depth dโ€„=โ€„32. Asymptotically, the proof size and verifier work is O(dlogโ€†(Bn)), compared to ฮฉ(BNlogโ€†n) in prior work (for ring dimension N). Unlike prior schemes, Laminate utilizes the full SIMD capabilities of FHE for both the payload circuit evaluation and proof generation; adds only constant multiplicative depth on top of payload evaluation while performing Oฬƒ(n) FHE operations; eliminates the need for witness reduction; and is field-agnostic. The resulting cost of adding integrity to FHE, compared to assuming honest evaluation, is โ€„โˆผโ€„12ร— to โ€„โˆผโ€„36ร— overhead (for deep multiplication-heavy circuits of size 2ยฒโฐ), which is โ€„>โ€„500ร— faster than the state-of-the-art.

Image showing part 2 of abstract.

Image showing part 2 of abstract.

Laminate: Succinct SIMD-Friendly Verifiable FHE (Kabir Peshawaria, Zeyu Liu, Ben Fisch, Eran Tromer) ia.cr/2025/2285

22.12.2025 17:27 โ€” ๐Ÿ‘ 4    ๐Ÿ” 2    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

agreed. Although I would love to see it run in a TEE, same way Signal are doing theirs. Otherwise, we are still uploading our contacts to an untrusted server

17.12.2025 06:09 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Also wrote a blog post that explains the proof in a shorter format and with less formality

blog.zksecurity.xyz/posts/fri-se...

30.10.2025 15:24 โ€” ๐Ÿ‘ 4    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Trying to reduce some headaches!

30.10.2025 13:24 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Itโ€™s time to reveal the ZK Whiteboard S3 Module 1... because it's LIVE!

๐Ÿฅ๐Ÿฅ๐Ÿฅ๐Ÿฅ

How to Build Hash Functions, with Jean-Philippe (JP) Aumasson @aumasson.jp & @nicomnbl.bsky.social

Watch the full module here: zkhack.dev/whiteboard/s...

03.09.2025 08:08 โ€” ๐Ÿ‘ 4    ๐Ÿ” 3    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Time has changed

01.08.2025 08:15 โ€” ๐Ÿ‘ 13895    ๐Ÿ” 5086    ๐Ÿ’ฌ 70    ๐Ÿ“Œ 55
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Local-First with grjte and Goblin Oats - ZK PODCAST In this episode, Anna Rose and Nico Mohnblatt speak with Goblin Oats from Tonk and grjte from Bain Capital Crypto [โ€ฆ]

The ZK Podcast released an episode on local-first software this week!

@arro.bsky.social and @nicomnbl.bsky.social chat w @grjte.sh & @goblinoats.com about the foundations of local-first architecture, CRDTs and how ZK can be incorporated into these models.

zeroknowledge.fm/podcast/367/

10.07.2025 16:49 โ€” ๐Ÿ‘ 15    ๐Ÿ” 5    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 3

Is this available on iOS too?

23.06.2025 19:50 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Don't think this was the case for everyone but for me it was about keeping my phone number private (before Signal introduced usernames)

23.06.2025 19:45 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

I'm kind of conflicted over this.

Up to now my Signal has been almost exclusively for personal use and Telegram exclusively for connecting at conferences. And I've come to value this clean separation

To the point where I have said no to connecting over Signal

23.06.2025 15:33 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 2    ๐Ÿ“Œ 0
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A Deep Dive into Logjumps: a Faster Modular Reduction Algorithm Logjumps is a recently discovered technique for modular reduction over large prime fields.

2/ As such, I wrote a research note to help cryptography engineers fully understand both techniques: baincapitalcrypto.com/a-deep-dive-...

11.06.2025 00:40 โ€” ๐Ÿ‘ 3    ๐Ÿ” 1    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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lattirust Lattice zero-knowledge/succinct arguments, and more - lattirust

I'm happy to finally open-source lattirust, a library for lattice-based zero-knowledge/succinct arguments! Lattirust is somewhat like arkworks, but for lattices; and like lattigo, but for arguments.

โž” github.com/lattirust

20.05.2025 14:55 โ€” ๐Ÿ‘ 32    ๐Ÿ” 16    ๐Ÿ’ฌ 2    ๐Ÿ“Œ 0

I wrote a thing on my colleagues Andrija and Guille's latest work

09.05.2025 16:09 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Video or it didn't happen ๐Ÿ‘€

07.05.2025 12:28 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Story of the ZK whiteboard series S2! The grant that supported it, how we came up with the topics, participation of our esteemed speakers, some crazy editing and how the bonus modules came to be

03.03.2025 18:49 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

But this might not work in your case depending on how strict you want to be on the caveat you mentioned

28.02.2025 14:30 โ€” ๐Ÿ‘ 3    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

The usual pattern is:
1. arrange the keys into a Merkle tree and give each signer their authentication path in that tree
2. signer produces a signature on the data
3. signer produces a ZKP that signature verifies against some public key, and that this public key is included in the Merkle tree

28.02.2025 14:29 โ€” ๐Ÿ‘ 3    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Part 2 starts with important terminology (pre-quantum vs post-quantum vs quantum). Or then explains how to make Bitcoin and Ethereum post-quantum secure via signature lifting and then talks about using quantum computers to make digital money

zeroknowledge.fm/podcast/297/

2/2

26.02.2025 15:20 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

from the archive: Or Sattath came on the ZKPodcast to discuss quantum computing and its impact on cryptography. These two are some of my ๐Ÿ๐š๐ฏ๐จ๐ฎ๐ซ๐ข๐ญ๐ž episodes of the show.

Part 1 covers the computation model, why it breaks some cryptography and effects on mining

zeroknowledge.fm/podcast/288/

1/2

26.02.2025 15:20 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

A step towards fixing the recent attack on a Fiat-Shamir'd variant of GKR.

Tl;dr: do proof-of-work before deriving the FS challenge, this will make the hash prohibitively expensive to compute in-circuit.

Caveat: they only prove the security of their transform for 1-round protocols

25.02.2025 16:01 โ€” ๐Ÿ‘ 0    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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sigh

23.02.2025 01:20 โ€” ๐Ÿ‘ 5    ๐Ÿ” 2    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Correct!

22.02.2025 10:13 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Terrible news

21.02.2025 16:31 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Sublinear prover?!?! Incredible result!

17.02.2025 06:52 โ€” ๐Ÿ‘ 7    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Bit of a tradeoff. We have O(1) proofs and verifiers using univariate polynomials, whereas sumcheck gives at best O(log(circuit))

07.02.2025 23:42 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

It replaces the "quotient polynomial". This was the method used to succinctly check that all the Plonk contraints or AIR rows are satisfied.

The advantage is that with sumcheck the prover no longer needs to perform polynomial division and therefore can run in linear time

06.02.2025 02:17 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

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