Production-ready, framework-agnostic SDK for building confidential dApps with Fully Homomorphic Encryption

✨ Fully compatible with Zama FHEVM v0.9 specification

🌐 Live Demo: https://jobjab-fhevm-react-template-nextjs.vercel.app/
📦 npm Package: https://www.npmjs.com/package/jobjab-fhevm-sdk
🎬 Video Walkthrough: https://www.youtube.com/watch?v=ASWVwOE1iPk
📚 Full Documentation: https://github.com/jobjab-dev/fhevm-react-template/tree/main/docs

Works with: React • Vue • Node.js • Vanilla JS • Any JavaScript framework

Prerequisites: Node.js ≥ 20.0.0 + pnpm

git clone https://github.com/jobjab-dev/fhevm-react-template
cd fhevm-react-template

Terminal 1 - Start blockchain:

pnpm chain

Terminal 2 - Run demo:

pnpm all:demo
# Installs → Builds SDK → Deploys contracts → Starts app

Try it:

1. Open http://localhost:3000
2. Connect MetaMask to Hardhat Local
3. Import test account: 0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80
4. Increment counter → Decrypt → See your private value! ✅

import { FhevmProvider, useEncrypt, useDecrypt } from 'jobjab-fhevm-sdk/adapters/react';
import { EncryptedInput, DecryptButton } from 'jobjab-fhevm-sdk/components/react';

// 1. Wrap app
<FhevmProvider config={{ network: 'sepolia' }}>
  <YourApp />
</FhevmProvider>

// 2. Use hooks
function MyComponent() {
  const { encrypt } = useEncrypt({ contractAddress: '0x...', userAddress: '0x...' });
  
  return (
    <EncryptedInput 
      type="euint32"
      onEncrypted={(r) => console.log('Encrypted!', r)}
    />
  );
}

📖 Full Guide: packages/fhevm-sdk/README.md

import { createFhevmClient } from 'jobjab-fhevm-sdk/core';

const client = await createFhevmClient({ network: 'sepolia' });

const result = await client.encrypt(
  '0xContract',
  '0xUser',
  { type: 'euint32', value: 42 }
);

await contract.myFunction(result.handles[0], result.inputProof);

📖 Example: examples/nodejs/

cd packages/cli && pnpm install && pnpm build

./dist/cli.js init           # Setup
./dist/cli.js encrypt 42     # Encrypt value
./dist/cli.js decrypt 0x...  # Decrypt  
./dist/cli.js check          # Health check

📖 CLI Guide: packages/cli/README.md

Core SDK:

• Framework-agnostic (React, Vue, Node.js, Vanilla JS)
• Wagmi-like API (Provider + hooks)
• Complete encrypt/decrypt flows
• Error handling with helpful messages

Components:

• <EncryptedInput> - Auto-encrypting form input
• <DecryptButton> - One-click decrypt with EIP-712
• <CipherPreview> - Display ciphertext info

Developer Tools:

• CLI: fhevm init, encrypt, decrypt, check
• Scripts: pnpm all:demo (one-shot setup)
• Performance: Batch operations (3-5x faster)

Quality:

• 142+ tests passing
• Full TypeScript support
• Comprehensive test coverage

Live Showcase:

• 🔢 Private Counter - Fully functional encrypted counter with increment/decrement
• 📖 More Showcase Ideas - Secret Bidding, Private Poll concepts

This SDK is designed for Zama FHEVM v0.9 specification:

✅ Modern Decryption Flow

• Uses relayer/KMS gateway architecture (v0.9)
• No deprecated FHE.requestDecryption or FHE.setDecryptionOracle
• Simplified EIP-712 (no contractsChainId field)

✅ Type System

• Primary types: ebool, euint8-256, eaddress (v0.9 spec)
• Legacy ebytes* marked deprecated (v0.7+ removal)
• Uses externalE* + inputProof pattern (ZKPoK)

✅ Network Support

• Sepolia testnet (official contract addresses)
• Localhost/Hardhat (auto-detection)
• Custom networks (gateway chain support)

✅ ACL & Permissions

• Works with FHE.allow, FHE.allowThis
• Supports FHE.makePubliclyDecryptable for reveal patterns

Verified with: @zama-fhe/relayer-sdk@0.2.0 | View Compatibility Details →

3-Step Process:

1. Encrypt → Client-side encryption with SDK
2. Compute → Encrypted operations on-chain
3. Decrypt → User reveals with EIP-712 signature

// Encrypt
const enc = await client.encrypt(addr, user, { type: 'euint32', value: 42 });

// Use in contract
await contract.increment(enc.handles[0], enc.inputProof);

// Decrypt to view
const result = await client.decrypt([{ handle, contractAddress }], signature);

📖 Learn More: QUICKSTART.md | COOKBOOK.md | Examples

# One-shot
pnpm all:demo       # Everything at once

# Development
pnpm chain          # Start blockchain
pnpm contracts:all  # Deploy contracts
pnpm start          # Start app

# SDK
pnpm sdk:build      # Build
pnpm sdk:test       # Test (142+ tests)

# CLI
fhevm init          # Setup
fhevm encrypt 42    # Encrypt
fhevm check         # Health check

packages/
├── fhevm-sdk/    ⭐ Universal SDK (publishable to npm)
├── cli/          ⚡ Command-line tool
├── nextjs/       🎨 Next.js demo (Private Counter)
└── hardhat/      🔧 Smart contracts

examples/
├── 01-10.ts      📝 10 TypeScript examples
├── nodejs/       🟢 Node.js server
├── vanilla-js/   🌐 Browser app
├── vue/          💚 Vue 3 Composition API
└── showcase/     💡 dApp ideas

Includes: SDK • CLI • Contracts • Next.js Demo • 4 Framework Examples • 10 Code Examples

🎨 Live Demo: Private Counter on Vercel → | 💡 More Ideas: Secret Bidding, Private Poll →

• Zama Documentation
• Zama Discord
• Developer Program

SDK Capabilities:

• ✅ Framework-agnostic core (works anywhere)
• ✅ React hooks & components (wagmi-like API)
• ✅ Batch encryption (3-5x faster)
• ✅ User & public decryption (via relayer/gateway)
• ✅ FHEVM v0.9 compliant decryption flow
• ✅ CLI tool (4 commands)
• ✅ 57 error codes with helpful messages
• ✅ Full TypeScript support
• ✅ 142+ tests passing

📋 See Complete Feature List →

Use Cases:

• 🎲 Confidential Prediction Markets - Private bets, fair outcomes
• 🗳️ Secret Voting/Polls - Anonymous voting without trust
• 🎯 Private Auctions - Sealed-bid without oracle dependency
• 💰 Encrypted DeFi - Private balances and transactions

📚 See Prediction Market MVP Guide →

BSD-3-Clause-Clear - See LICENSE

Built with Zama's FHEVM - the leading Fully Homomorphic Encryption solution for Ethereum.

Special thanks to the Zama team for pioneering confidential smart contracts and the FHE ecosystem.

Contributions are welcome! Please read our contributing guidelines and submit pull requests.

For major changes, please open an issue first to discuss proposed changes.

Built with ❤️ for the Zama community