Installation

Install and configure the Privacy Cash SDK

Prerequisites

Before installing the SDK, ensure you have the following:

Node.js

Version 16 or later

Solana CLI

Version 2.1.18 or later

Anchor

Version 0.31.1 (for development)

TypeScript

Recommended for type safety

Install the SDK

The Privacy Cash SDK is available on GitHub. Install it using npm or yarn:

npm

npm install @privacy-cash/sdk

yarn add @privacy-cash/sdk

pnpm add @privacy-cash/sdk

The SDK package is hosted at github.com/Privacy-Cash/privacy-cash-sdk.

Install Dependencies

The SDK requires several peer dependencies for cryptographic operations:

npm

npm install @coral-xyz/anchor @solana/web3.js @solana/spl-token \
  @lightprotocol/hasher.rs snarkjs ffjavascript bn.js borsh \
  @ethersproject/sha2

yarn add @coral-xyz/anchor @solana/web3.js @solana/spl-token \
  @lightprotocol/hasher.rs snarkjs ffjavascript bn.js borsh \
  @ethersproject/sha2

Dependency Overview

Package	Purpose
@coral-xyz/anchor	Solana program interaction framework
@solana/web3.js	Solana blockchain interaction
@solana/spl-token	SPL token operations
@lightprotocol/hasher.rs	Poseidon hash implementation (WASM)
snarkjs	Zero-knowledge proof generation
ffjavascript	Finite field arithmetic
bn.js	Big number operations
borsh	Binary serialization
@ethersproject/sha2	SHA-256 hashing

Download Circuit Files

The SDK requires circuit files for proof generation. These are large files (100MB+) and must be downloaded separately:

1. Clone the Repository

   git clone https://github.com/Privacy-Cash/privacy-cash
   cd privacy-cash
   
2. Build Circuit Artifacts

   cd anchor/circuits
   # Install circom if not already installed
   # See: https://docs.circom.io/getting-started/installation/
   
   # Compile the circuit
   circom transaction2.circom --r1cs --wasm --sym
   
   # Generate proving and verification keys
   # This requires a trusted setup ceremony (powers of tau)
   snarkjs groth16 setup transaction2.r1cs pot_final.ptau transaction2.zkey
   
3. Copy Artifacts to Your Project

   mkdir -p your-project/circuits
   cp artifacts/circuits/transaction2/transaction2.wasm your-project/circuits/
   cp artifacts/circuits/transaction2/transaction2.zkey your-project/circuits/
   

Circuit files are typically 100-500MB in size. Ensure you have sufficient disk space and bandwidth.

Initialize the SDK

Create a configuration file to initialize the SDK:

config.ts

import { Connection, PublicKey } from '@solana/web3.js';
import { AnchorProvider, Program } from '@coral-xyz/anchor';
import { WasmFactory } from '@lightprotocol/hasher.rs';

// Initialize connection
const connection = new Connection('https://api.mainnet-beta.solana.com', 'confirmed');

// Initialize Poseidon hasher
const lightWasm = await WasmFactory.getInstance();

// Program ID
const PROGRAM_ID = new PublicKey('9fhQBbumKEFuXtMBDw8AaQyAjCorLGJQiS3skWZdQyQD');

// Circuit paths
const CIRCUIT_WASM = './circuits/transaction2.wasm';
const CIRCUIT_ZKEY = './circuits/transaction2.zkey';

export { connection, lightWasm, PROGRAM_ID, CIRCUIT_WASM, CIRCUIT_ZKEY };

Verify Installation

Test your installation with a simple script:

test-installation.ts

import { WasmFactory } from '@lightprotocol/hasher.rs';
import { Utxo } from '@privacy-cash/sdk';
import BN from 'bn.js';

async function testInstallation() {
  // Initialize hasher
  const lightWasm = await WasmFactory.getInstance();
  
  // Create a test UTXO
  const utxo = new Utxo({
    lightWasm,
    amount: new BN(1000000), // 0.001 SOL
  });
  
  // Generate commitment
  const commitment = await utxo.getCommitment();
  console.log('UTXO commitment:', commitment);
  
  // Generate nullifier
  const nullifier = await utxo.getNullifier();
  console.log('UTXO nullifier:', nullifier);
  
  console.log('✅ Installation verified successfully!');
}

testInstallation().catch(console.error);

Run the test:

ts-node test-installation.ts

If you see commitment and nullifier outputs, your installation is complete!

Environment Configuration

Create a .env file for sensitive configuration:

.env

# Network Configuration
SOLANA_RPC_URL=https://api.mainnet-beta.solana.com
CLUSTER=mainnet-beta

# Program ID
PROGRAM_ID=9fhQBbumKEFuXtMBDw8AaQyAjCorLGJQiS3skWZdQyQD

# Circuit Files
CIRCUIT_WASM_PATH=./circuits/transaction2.wasm
CIRCUIT_ZKEY_PATH=./circuits/transaction2.zkey

# Fee Configuration
FEE_RECIPIENT=AWexibGxNFKTa1b5R5MN4PJr9HWnWRwf8EW9g8cLx3dM

Never commit private keys or seed phrases to version control. Use environment variables or secure key management systems.

TypeScript Configuration

Add proper TypeScript configuration for the SDK:

tsconfig.json

{
  "compilerOptions": {
    "target": "ES2020",
    "module": "commonjs",
    "lib": ["ES2020"],
    "moduleResolution": "node",
    "esModuleInterop": true,
    "skipLibCheck": true,
    "strict": true,
    "resolveJsonModule": true,
    "outDir": "./dist",
    "rootDir": "./src"
  },
  "include": ["src/**/*"],
  "exclude": ["node_modules"]
}

Next Steps

Basic Usage

Learn core SDK operations

Examples

View complete integration examples