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educative · zk · halo2

Become a Halo2 Hero: Master Zero-Knowledge Proofs with Our New Course

Halo2 course

In collaboration with the Zircuit development team, we are excited to announce the release of a course on Halo2 development. Unlike the excellent Halo2 book which focuses on the proof system itself, this course focuses on teaching Rust developers how to develop Halo2 circuits from scratch -- without any prior knowledge of Halo2, PlonK or developing circuits for zkSNARKs required. You don't need to be a cryptographer to follow along! We start from the very basics and build up to more complex circuits with lookups, challenges and more. At the end of the course, you should become a true Halo Hero!

All code in the course comes with complete runnable examples available in the accompanying GitHub repository. This means that any code snippet in the course can be run as a self-contained example!

Get started with Halo2 development today at halo2.zksecurity.xyz.

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Halo2's Elegant Transcript As Proof

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David Wong · September 30, 2025

Uncovering the Query Collision Bug in Halo2: How a Single Extra Query Breaks Soundness

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Suneal Gong · July 09, 2025

𝒫𝔩𝔬𝔫𝒦: A Hands-On Deep Dive

𝒫𝔩𝔬𝔫𝒦’s many layers (selector polynomials, wiring permutations, quotient tests, random challenges and KZG commitments) can be overwhelming. Our zkSecurity tutorial uses a single running example to demystify them all. Build tables and interpolate low-degree BN254 polynomials, encode gate and wiring constraints, run deterministic and probabilistic zero-tests, then layer in randomness and KZG commitments to produce a full Fiat–Shamir proof. Grab the Jupyter Notebook (Sage or Cocalc), or work in your favorite language with our guided test cases.

Martín Ochoa · August 05, 2025
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Sum-Check as an Algebraic Tensor Reduction: Part III

This post is all about the maps that let us move between modules without breaking their structure. We’ll see when a map is truly “linear,” when two modules are (secretly) the same, and why two-input maps deserve special attention. Along the way, (bi-)linear maps and isomorphisms become less like abstract definitions and more like tools we can actually use. By the end, we’ll have all the tooling we need to tackle abstract tensor products head-on.

Marco Besier · May 18, 2026

Public report of Sui's zkLogin audit

We just finished an audit of the Sui Foundation's zkLogin application and we're sharing what we found: the code is well-documented, tested, and specified. The zkLogin is set to make user authentication on the blockchain secure but simple, replacing cryptographic keys with familiar SSO methods like Google or Facebook while preserving user privacy. We also dive into the technical details behind JWT verification, non-native arithmetic for RSA, and vector programming. Plus, learn about the trusted setup process for zkLogin, ensuring maximum security through a decentralized multi-party ceremony. If you're curious about the intricate mechanics behind zkLogin, this is a must-read.

ZK/SEC · November 07, 2023

Circle STARKs: Part IV, Arithmetizing Circles

In this final part of our series on Circle STARKs, we tie together concepts from Mersenne prime fields, circle curves and bivariate polynomials to showcase a comprehensive Circle STARK protocol. We detail the process of arithmetization over the circle curve, introducing Circle FRI as a low-degree test and walk through the complete Circle STARK construction. Readers will explore how trace commitments, constraint batching and low-degree proofs combine for efficient verifiable computation, delving into the nuances of proof validity and security analysis.

Varun Thakore · November 17, 2025