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Archetype X zkSecurity - Proof Is in the Pudding: Privacy in Payment Networks

ZK/SEC January 16, 2026 1 min read
educative zk privacy

For the 8th session of Proof is in the Pudding, we teamed up with Archetype to explore the fascinating world of privacy in payment networks.

There's no single best approach to privacy, but there's no shortage of interesting techniques that have been developed over the years to break linkability, hide addresses, and obscure transaction data. In this session, we take a comprehensive tour through the evolution of private payment systems, covering E-Cash, blind signatures, Bitcoin privacy, confidential transactions and Pedersen commitments, Mimblewimble, Monero, stealth addresses, ring signatures, MobileCoin and TEEs, Zcash, and Zether.

If you enjoy this video, check out our previous episodes:

zkSecurity offers auditing, research, and development services for cryptographic systems including zero-knowledge proofs, MPCs, FHE, consensus protocols and more.

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Sum-check as an Algebraic Tensor Reduction: Part II

Marco Besier May 10, 2026
sum-check algebraic reductions of knowledge tensors rings modules

In this part of our series, we start introducing the algebraic language needed to formalize sum-check as a tensor reduction. We start with the basics of rings and modules. Rings generalize fields by dropping the requirement that every non-zero element has a multiplicative inverse. Modules then generalize vector spaces by allowing scalars to come from a ring instead of a field. In this post, we’ll use plenty of examples to make these ideas concrete and build intuition along the way.

Breaking Jolt’s Verifier with an Unbound Uni-skip Claim

Minsun Kim May 09, 2026
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We found a critical soundness bug in Jolt’s transparent verifier that allowed a forged proof for an invalid execution to verify. The issue was fixed quickly after disclosure, and the full PoC and write-up are available in the linked repository.

Notes and Proofs for Divisor Techniques

Mathias Hall-Andersen May 08, 2026
educative zk elliptic-curves monero

Notes and proofs for the divisor-based ECIP protocol of Eagen, written with Diego F. Aranha and supported by MAGIC Grants. The document is self-contained: it works through the necessary algebraic geometry, the interactive proof and its soundness, the composition with a simulation-extractable NIZK, and the R1CS verifier circuit used by Parker's gadget in Monero's FCMP++.

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Archetype X zkSecurity - Proof Is in the Pudding: the Other Dark Forest (Offchain Public Keys)

ZK/SEC October 21, 2025
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In Session 07 of "Proof is in the Pudding," we explore the other dark forest, the realm of offchain public keys. We dive into zkLogin, ZK Email, and ZKPassport, examining how these protocols handle authentication and privacy. We also discuss the issue of unlinkability in privacy protocols and why replacing traditional signature verifications with zero-knowledge proofs could unlock more interesting and powerful ZK products.

Archetype X zkSecurity - Proof in the Pudding: Introduction to Data Availability (Sampling)

ZK/SEC October 02, 2025
educative zk data-availability

In the latest "Proof is in the Pudding" session, we team up with Archetype to break down the essentials of Data Availability Sampling. We dive into how rollups and Ethereum's DA system work, explore the role of DA chains, and touch on the basics of verifiable sharding. This introduction is perfect for anyone curious about the foundations of data availability sampling and how these concepts are playing out in the blockchain world.

Archetype X zkSecurity (Whiteboard Session) - Proof Is in the Pudding: How to Prove False Statements

ZK/SEC February 25, 2025
educative security zk gkr

In our third whiteboard session with Archetype, we dive into the fascinating world of cryptographic protocols by breaking down the intricacies of the Fiat-Shamir security model and the GKR protocol. Whether you're a cryptography enthusiast or just curious about how these complex mechanisms enhance security, this is a chance to explore the theories with us in a friendly and digestible way. Don't miss the opportunity to expand your understanding of this cutting-edge topic!

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Circle Starks: Part II, Circles

Varun Thakore, Mathias Hall-Andersen February 21, 2025
educative zk fri

In this blog post, we dive into the fascinating world of Circle STARKs, exploring the algebra of complex numbers and how they can be extended to any field. We revisit the concept of the unit circle and its unique group structure, which allows for cool operations like squaring and doubling angles. You'll discover how these ideas apply to finite fields, creating intriguing structures like the twin-coset and standard position coset. The post leads us to understand vanishing polynomials, crucial in STARKs, and sets the stage for exploring the circle FFT in upcoming discussions. Perfect for anyone curious about cutting-edge cryptographic techniques!

Powers-of-funbenius

Mathias Hall-Andersen May 05, 2026
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A one-character repeated-squaring bug in Inferno's Limbo implementation turns the intended random polynomial check into a linearized Frobenius check over a binary extension field. This post walks through why the usual Schwartz-Zippel argument disappears, how periodicity of the Frobenius map makes collisions immediate after 64 multiplication gates, and how even smaller circuits can cheat with noticeably higher probability.

Noname 3.0: Native Hints, Standard Library, Compiler Visualizer, and More!

ZK/SEC November 13, 2024
announcement tools zk

We're super excited to introduce noname 3.0, our zk programming language inspired by Rust and Golang, now achieving full feature parity with Circom. This update brings native hints, a standard library, debugging features, and a lot more to enhance developer experience. Dive into how hint functions work with an 'unsafe' keyword to balance innovation and security, explore our new stdlib modules, and see how the compiler pipeline visualizer can help you understand the compiling process. Plus, check out our next steps and how you can contribute to shaping noname's future.
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