Zerokit provides zero-knowledge cryptographic primitives with a focus on performance, security, and usability. The current focus is on Rate-Limiting Nullifier RLN implementation.

Current implementation is based on the following specification and focused on RLNv2 which allow to set a rate limit for the number of messages that can be sent by a user.

Features

RLN Implementation: Efficient Rate-Limiting Nullifier using zkSNARKs
Circom Compatibility: Uses Circom-based circuits for RLN
Cross-Platform: Support for multiple architectures (see compatibility note below)
FFI-Friendly: Easy to integrate with other languages

Architecture

Zerokit currently focuses on RLN (Rate-Limiting Nullifier) implementation using Circom circuits through ark-circom, providing an alternative to existing native Rust implementations.

Build and Test

Important

For WASM support or x32 architecture builds, use version 0.6.1. Current version has dependency issues for these platforms. WASM support will return in a future release.

Install Dependencies

make installdeps

Build and Test All Crates

make build
make test

Release Assets

We use cross-rs to cross-compile and generate release assets:

# Example: Build for specific target
cross build --target x86_64-unknown-linux-gnu --release -p rln

Used By

Zerokit powers zero-knowledge functionality in:

nwaku - Nim implementation of the Waku v2 protocol
js-rln - JavaScript bindings for RLN

Acknowledgements

Inspired by Applied ZKP group work, including zk-kit
Uses ark-circom for zkey and Groth16 proof generation
Witness calculation based on circom-witnesscalc by iden3. The execution graph file used by this code has been generated by means of the same iden3 software.

Important

The circom-witnesscalc code fragments have been borrowed instead of depending on this crate, because its types of input and output data were incompatible with the corresponding zerokit code fragments, and circom-witnesscalc has some dependencies, which are redundant for our purpose.

Documentation

For detailed documentation on each module:

cargo doc --open