CIRCUIT COMPILER FOR ZK PROVING SYSTEMS

Circom is a novel domain-specific language for defining arithmetic circuits that can be used to generate zero-knowledge proofs. Circom compiler is a circom language compiler written in Rust that can be used to generate a R1CS file with a set of associated constraints and a program (written either in C++ or WebAssembly) to efficiently compute a valid assignment to all wires of the circuit. One of the main particularities of circom is its modularity that allows the programmers to define parameterizable circuits called templates, which can be instantiated to form larger circuits. The idea of building circuits from small individual components makes it easier to test, review, audit, or formally verify large and complex circom circuits. In this regard, circom users can create their own custom templates or instantiate templates from circomLib, a publicly available library that counts with hundreds of circuits such as comparators, hash functions, digital signatures, binary and decimal converters, and many more. Circomlib is publicly available to practitioners and developers.

The implementations of proving systems are also available in our libraries including snarkjs, written in Javascript and Pure Web Assembly, wasmsnark written in native Web Assembly, rapidSnark written in C++ and Intel Assembly.

Circom aims to provide developers a holistic framework to construct arithmetic circuits through an easy-to-use interface and abstracting the complexity of the proving mechanisms.

Circom language reference can be found at circom language reference

At this time there are two available syntax highlighters: circom Visual Studio Code highlight syntax and circom Vim highlight syntax

All documentation is available in circom 2 Documentation, we encourage you to read it. If you are new start with the Getting started section. Basic background on Zero-knowledge proofs can be found on Background section

Refer to Installation section

The previous circom 1 compiler written in Javascript is deprecated, but circom 1 repository is still available

Thank you for considering contributing to the circom & snarkjs framework!

As the circom and snarkjs community grows new tools, circuits, or projects have appeared. Here we link some of them:

CIRCUITS

• 0xPARC circom ECDSA circuit

TOOLS

• zkREPL an online playground for zk circuits