Circuits for zkEVM

This is the zkEVM circuits used in Scroll Mainnet. It was forked from PSE zkevm-circuits and added a lot of new features later:

1. SHA256 / MODEXP / EC precompiles
2. RLP circuit / MPT circuit / Poseidon circuit
3. multi block chunking
4. proof aggregation
5. >99.5% compatibility with official EVM test vector
6. Many optimizations like read/write memory in word instead of byte

Docs

High level design: https://docs.scroll.io/en/technology/zkevm/zkevm-overview/
Detailed circuit docs: https://github.com/scroll-tech/zkevm-circuits/tree/develop/docs

Getting started

We recommend developers to go to our circuit playground repo for a detailed step-by-step guide on how to run proving.

Project Layout

This repository contains several Rust packages that implement the zkevm. The high-level structure of the repository is as follows:

bus-mapping

• a crate designed to parse EVM execution traces and manipulate all of the data they provide in order to obtain structured witness inputs for circuits.

circuit-benchmarks

• (Deprecated) Measures performance of each circuit based on proving and verifying time and execution trace parsing and generation for each subcircuit

eth-types

• Different types helpful for various components of the EVM

external-tracer

• Generates traces by connecting to an locally linked Geth EVM tracer

gadgets

• Custom circuits that abstracts away low-level circuit detail.
• What are gadgets?

geth-utils

• Provides output from geth tracing APIs as circuit inputs

integration-tests

• Integration tests for all circuits

keccak256

• (Deprecated) Modules for Keccak hash circuit

mock

• Testing module. Mock definitions and methods that are used to test circuits or opcodes

testool

• Parser and driver of official Ethereum Execution Tests

zkevm-circuits

• Main package that contains all circuit logic

zktrie

• Wrapper of scroll binary poseidon trie