rSnark

Write zero-knowledge circuits in Rust for multiple prover systems.

rSnark is a Rust library for writing zero-knowledge circuits and generating proofs. It provides a core library to write circuits and a provers library to generate proofs using various backend implementations like Gnark.

Features

• Simple Circuit Definition: Use derive macros to easily define circuits
• Multiple Backend Support: Write circuit once, prover on multiple prover system
• Nested Circuits: Compose complex circuits from simpler ones
• Type Safety: Leverage Rust's type system for circuit safety

Getting Started

Add rSnark to your Cargo.toml:

[dependencies]
rsnark = "0.1.0"

or use cargo add:

cargo add rsnark

Writing Your First Circuit

Defining a circuit requires two simple steps:

1. Define the circuit's inputs and outputs using the #[derive(Circuit)] macro
2. Implement the Circuit trait to define the circuit's constraint rules

use rsnark::{
    Groth16BN254GnarkProver,
    core::{API, Circuit, CircuitDefine, CircuitWitness},
};

#[derive(Circuit)]
pub struct TestCircuit {
    a: u32,        // private input
    b: u32,        // private input  
    pub c: u32,    // public input
}

impl Circuit for CircuitDefine<TestCircuit> {
    fn define(&self, api: &mut impl API) {
        let c = api.add(&self.a, &self.b);
        api.assert_is_equal(&c, &self.c);
    }
}

Circuit Visibility Rules

The #[derive(Circuit)] macro treats Rust's visibility modifiers as indicators:

• Fields without pub are treated as private inputs
• Fields with pub are treated as public inputs

Supported Prover Triples

Similar to compiler target triples, rSnark uses backend triples to define which backend, curve, and proving system to use. The format is: {proving_system}-{curve}-{backend}.

Currently supported backend triples:

Project Structure

This workspace contains several crates:

• rsnark - Main library and unified API
• rsnark-core - Core circuit definition and API traits
• rsnark-macros - Derive macros for circuit definition
• rsnark-provers-core - Common prover traits and interfaces
• rsnark-provers-gnark - Gnark backend implementation
• rsnark-provers-mock - Mock prover for testing

Examples

Check out the examples/ directory for more detailed examples of how to use rSnark.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.