react-native-dop-prover

Native ZK witness generator for DOP Protocol. Generates witnesses natively on mobile devices for fast zero-knowledge proof generation.

Features

• 66 transfer circuits - All DOP transfer variants from 1x0 to 13x1
• Native performance - 10-50x faster than JavaScript WASM execution
• Hardware-accelerated - Compiled to native ARM/x86 code
• Proper .wtns format - Compatible with snarkjs and rapidsnark
• TypeScript support - Full type definitions included

Supported Circuits

| Inputs | Outputs 0 | 1 | 2 | 3 | 4 | 5 | 10 | 13 | |--------|-----------|---|---|---|---|---|----|----| | 1 | Y | Y | Y | Y | Y | Y | Y | Y | | 2 | Y | Y | Y | Y | Y | Y | | | | 3 | Y | Y | Y | Y | Y | Y | | | | 4 | Y | Y | Y | Y | Y | Y | | | | 5 | Y | Y | Y | Y | Y | Y | | | | 6 | Y | Y | Y | Y | Y | Y | | | | 7 | Y | Y | Y | Y | Y | Y | | | | 8 | Y | Y | Y | Y | Y | Y | | | | 9 | Y | Y | Y | Y | Y | Y | | | | 10 | Y | Y | Y | Y | Y | | | | | 11 | Y | Y | | | | | | | | 12 | Y | Y | | | | | | | | 13 | | Y | | | | | | |

Total: 66 circuits

Installation

npm install react-native-dop-prover
# or
yarn add react-native-dop-prover

Download Native Libraries

Native libraries (~1GB total) are not included in the git repo. Download from GitHub Releases:

# Build locally (requires Rust + Android NDK):
cd /path/to/mopro-dop
./build_all_android.sh
cp -r jniLibs/* /path/to/react-native-dop-prover/android/src/main/jniLibs/

iOS Setup

cd ios && pod install

Android Setup

Ensure native libraries exist in:

• android/src/main/jniLibs/arm64-v8a/libdop_mobile_prover.so (64-bit ARM)
• armeabi-v7a (32-bit ARM)
• x86_64 (Emulator)

Usage

Basic Example

import DopProver from 'react-native-dop-prover';

// Check supported circuits
const circuits = await DopProver.getSupportedCircuits();
console.log(`Supported: ${circuits.length} circuits`);

// Calculate witness
const witness = await DopProver.calculateWitness('transfer_1x2', inputs);
console.log(`Witness elements: ${witness.length}`);

Full Transaction Example

import DopProver from 'react-native-dop-prover';

const inputs = {
  merkleRoot: '6222425295742392060788226778694769114506305024317843914902643617290374768963',
  boundParamsHash: '5710287756984354871128133611023121898130345951914076394217910154190632022267',
  nullifiers: ['2488005839880174281371566850742862351218389849446606448043615745372921337838'],
  commitmentsOut: [
    '14442913796384197520571496765626647486596829362832619910396444542983171421557',
    '19252303434306434500840759223364185816884050656317846745992399487059334764561',
  ],
  token: '546584486846459126461364135121053344201067465379',
  publicKey: [
    '15684838006997671713939066069845237677934334329285343229142447933587909549584',
    '11878614856120328179849762231924033298788609151532558727282528569229552954628',
  ],
  signature: [
    '16927417158026668872034053079746879482505341725377973536231219666755150412517',
    '4460683417520795250530582144217697783429941348945040786207839936208783640494',
    '323943078793744741814096352565656579413445122634109055822579790017960112397',
  ],
  randomIn: ['40419079083657351839989032552519750558'],
  valueIn: ['9975062344139650872817'],
  pathElements: [
    '2051258411002736885948763699317990061539314419500486054347250703186609807356',
    // ... 16 elements total (Merkle proof path)
  ],
  leavesIndices: ['0'],
  nullifyingKey: '8368299126798249740586535953124199418524409103803955764525436743456763691384',
  npkOut: [
    '18155422517519710121567557298796336647851001757086572188586973563076356884330',
    '14453327337221153863920321130101533812935021152859474978476854443074076494952',
  ],
  valueOut: ['65000000000000000000', '9910062344139650872817'],
};

// Calculate witness (returns decimal string array)
const witness = await DopProver.calculateWitness('transfer_1x2', inputs);

// Or get as .wtns bytes for rapidsnark
const witnessBytes = await DopProver.calculateWitnessAsBytes('transfer_1x2', inputs);

Integration with Proof Generation

import DopProver from 'react-native-dop-prover';
import { groth16 } from 'snarkjs';

async function generateProof(circuitName: string, inputs: any, zkeyPath: string) {
  // Step 1: Calculate witness natively (10-50x faster than JS)
  const startWitness = Date.now();
  const witnessBytes = await DopProver.calculateWitnessAsBytes(circuitName, inputs);
  console.log(`Witness: ${Date.now() - startWitness}ms`);
  
  // Step 2: Generate proof with rapidsnark/snarkjs
  // witnessBytes is in proper .wtns format
  const { proof, publicSignals } = await groth16.prove(zkeyPath, witnessBytes);
  
  return { proof, publicSignals };
}

API Reference

getSupportedCircuits(): Promise<string[]>

Returns list of all supported circuit names.

calculateWitness(circuit: string, inputs: object): Promise<string[]>

Calculate witness and return as array of decimal strings.

• circuit - Circuit name (e.g., 'transfer_1x2')
• inputs - Circuit inputs as JavaScript object
• Returns: Array of witness elements as decimal strings

calculateWitnessAsBytes(circuit: string, inputs: object): Promise<Uint8Array>

Calculate witness and return as .wtns binary format.

• circuit - Circuit name
• inputs - Circuit inputs
• Returns: Witness in snarkjs-compatible .wtns binary format

calculateWitnessJson(circuit: string, inputsJson: string): Promise<string>

Low-level JSON API for witness calculation.

calculateWitnessBytes(circuit: string, inputsJson: string): Promise<string>

Low-level API returning base64-encoded .wtns bytes.

Performance

Typical witness calculation times on modern devices:

| Circuit | iPhone 14 | Pixel 7 | |---------|-----------|---------| | transfer_1x1 | ~15ms | ~20ms | | transfer_1x2 | ~18ms | ~25ms | | transfer_5x5 | ~45ms | ~60ms | | transfer_10x4 | ~80ms | ~100ms |

Compared to JavaScript WASM: 10-50x faster

Error Handling

try {
  const witness = await DopProver.calculateWitness('transfer_1x2', inputs);
} catch (error) {
  // Possible errors:
  // - "Circuit not found: transfer_invalid"
  // - "Invalid input format"
  // - "Witness calculation failed: constraint not satisfied"
  console.error('Prover error:', error.message);
}

Building from Source

Requirements

• Rust toolchain (rustup)
• Android NDK 27+
• Xcode 14+ (for iOS)
• cargo-ndk (cargo install cargo-ndk)

Build Android

cd /path/to/mopro-dop
./build_android.sh

Build iOS

cd /path/to/mopro-dop
./build_ios.sh

Architecture

react-native-dop-prover/
  android/
    src/main/
      java/.../DopProverModule.java  # Android native module
      jniLibs/
        arm64-v8a/libdop_mobile_prover.so
        armeabi-v7a/libdop_mobile_prover.so
        x86_64/libdop_mobile_prover.so
  ios/
    DopProver.swift                   # iOS native module
    libdop_mobile_prover.a            # iOS static library
  src/
    index.ts                          # TypeScript API
    index.d.ts                        # Type definitions

License

MIT