zcash/halo2

The Halo2 zero-knowledge proving system

Rust

926

2,737 commits

updated Oct 16, 2026

See the code

README

halo2

Usage

This repository contains the halo2_proofs and halo2_gadgets crates, which should be used directly.

Minimum Supported Rust Version

Requires Rust 1.88 or higher.

Minimum supported Rust version can be changed in the future, but it will be done with a minor version bump.

Controlling parallelism

halo2 currently uses rayon for parallel computation. The RAYON_NUM_THREADS environment variable can be used to set the number of threads.

You can disable rayon by disabling the "multicore" feature. Warning! Halo2 will lose access to parallelism if you disable the "multicore" feature. This will significantly degrade performance.

License

Licensed under either of

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

cryptocurrency
cryptography
zcash
zero-knowledge

Project health

crates.io

Latest release

0.0.0 · May 11, 2020

Releases this year

0

Significant stargazers

(top 24 of 31)

adamnemecek

508 followers · starred May 2023

Justin Traglia

197 followers · starred May 2023

Ying Sheng

2,220 followers · starred Oct 2022

Zaki Manian

526 followers · starred Sep 2020

zcash/halo2

The Halo2 zero-knowledge proving system

Rust

926

2,737 commits

updated Oct 16, 2026

See the code

README

halo2

Usage

This repository contains the halo2_proofs and halo2_gadgets crates, which should be used directly.

Minimum Supported Rust Version

Requires Rust 1.88 or higher.

Minimum supported Rust version can be changed in the future, but it will be done with a minor version bump.

Controlling parallelism

halo2 currently uses rayon for parallel computation. The RAYON_NUM_THREADS environment variable can be used to set the number of threads.

You can disable rayon by disabling the "multicore" feature. Warning! Halo2 will lose access to parallelism if you disable the "multicore" feature. This will significantly degrade performance.

License

Licensed under either of

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

cryptocurrency
cryptography
zcash
zero-knowledge

Project health

crates.io

Latest release

0.0.0 · May 11, 2020

Releases this year

0

Significant stargazers

(top 24 of 31)

adamnemecek

508 followers · starred May 2023

Justin Traglia

197 followers · starred May 2023

Ying Sheng

2,220 followers · starred Oct 2022

Zaki Manian

526 followers · starred Sep 2020