Consensys/gnark

gnark zk-SNARK library

High-performance zk-SNARKs in Go.

gnark provides a high-level API to define circuits, then compile, prove, and verify with production-grade proving systems. It is open-source under Apache 2.0 and uses gnark-crypto for field arithmetic and cryptographic primitives.

gnark powers Linea zk-rollup. Include your project in known users by opening a PR.

Why gnark

• Circuit development in idiomatic Go
• Fast proving and verification backends
• Reusable standard gadgets in std/
• Active security and regression testing culture

Useful Links

• gnark User Documentation
• gnark Playground
• gnark Issues
• gnark Benchmarks 🏁
• gnark-announce - release and security announcements

Quick Start

Requirements

• Go 1.25+ (module target: go 1.25.7)

Install

go get github.com/consensys/gnark@latest

Run an example

go run ./examples/cubic

To design your first circuit, follow the tutorial in gnark User Documentation.

Supported Proving Systems and Curves

gnark currently supports:

• Groth16
• PLONK

on the following curves:

• BN254
• BLS12-381
• BLS12-377
• BW6-761

Notes:

• Solidity verifier export support is curve-dependent (BN254 is the primary target).
• Serialized formats are not guaranteed to be stable across versions.

GPU Acceleration (Experimental)

gnark includes experimental GPU acceleration through Ingonyama's ICICLE backend for Groth16 on:

• BN254
• BLS12-377
• BLS12-381
• BW6-761

See accelerated backend documentation and the ICICLE repository.

Example Circuit

The circuit below encodes x**3 + x + 5 == y.

package main

import (
	"github.com/consensys/gnark-crypto/ecc"
	"github.com/consensys/gnark/backend/groth16"
	"github.com/consensys/gnark/frontend"
	"github.com/consensys/gnark/frontend/cs/r1cs"
)

// CubicCircuit defines a simple circuit.
// x**3 + x + 5 == y
type CubicCircuit struct {
	X frontend.Variable `gnark:"x"`
	Y frontend.Variable `gnark:",public"`
}

// Define declares the circuit constraints.
func (circuit *CubicCircuit) Define(api frontend.API) error {
	x3 := api.Mul(circuit.X, circuit.X, circuit.X)
	api.AssertIsEqual(circuit.Y, api.Add(x3, circuit.X, 5))
	return nil
}

func main() {
	var circuit CubicCircuit
	ccs, _ := frontend.Compile(ecc.BN254.ScalarField(), r1cs.NewBuilder, &circuit)

	pk, vk, _ := groth16.Setup(ccs)

	assignment := CubicCircuit{X: 3, Y: 35}
	witness, _ := frontend.NewWitness(&assignment, ecc.BN254.ScalarField())
	publicWitness, _ := witness.Public()

	proof, _ := groth16.Prove(ccs, pk, witness)
	_ = groth16.Verify(proof, vk, publicWitness)
}

Security

gnark and gnark-crypto have been extensively audited, but are provided as-is with no guarantees or warranties. In particular, gnark does not guarantee constant-time implementations or side-channel resistance.

Report vulnerabilities via Security Policy. Do not open public issues for security reports.

Published advisories are listed here.

Testing

CI runs formatting, generated-file, lint, and test checks on pull requests and pushes.

Common local commands:

go test -short ./...
go test -tags=release_checks,solccheck .
go test -tags=prover_checks ./test/... ./examples/...
go test -run=NONE -fuzz=FuzzIntcomp -fuzztime=30s ./internal/backend/ioutils
go generate ./...

Audits

• Kudelski Security - October 2022 - gnark-crypto (contracted by Algorand Foundation)
• Sigma Prime - May 2024 - gnark-crypto KZG (contracted by Ethereum Foundation)
• Consensys Diligence - June 2023 - gnark PLONK Solidity verifier
• LeastAuthority - August 2023 - gnark Groth16 Solidity verifier template (contracted by Worldcoin)
• OpenZeppelin - November 2023 - gnark PLONK Solidity verifier template
• ZKSecurity.xyz - May 2024 - gnark standard library
• OpenZeppelin - June 2024 - gnark PLONK prover and verifier
• LeastAuthority - September 2024 - gnark general and GKR
• LeastAuthority - November 2024 - Linea zkEVM

Release Notes

See CHANGELOG.md.

Citing

If you use gnark in research, please cite the latest release:

@software{gnark-v0.15.0,
  author       = {Gautam Botrel and
                  Thomas Piellard and
                  Youssef El Housni and
                  Ivo Kubjas and
                  Arya Tabaie and
                  Yao J. Galteland},
  title        = {Consensys/gnark: v0.15.0},
  month        = may,
  year         = 2026,
  publisher    = {Zenodo},
  version      = {v0.15.0},
  doi          = {10.5281/zenodo.5819104},
  url          = {https://doi.org/10.5281/zenodo.5819104}
}

Contributing

See CONTRIBUTING.md and CODE_OF_CONDUCT.md.

Versioning

gnark follows SemVer. Available versions are in tags.

License

Licensed under Apache 2.0 (see LICENSE).