flash-usdt-sender

Unified multi-chain USDT transfer SDK for Ethereum, BNB Chain, and TRON

flash-usdt-sender is a production-grade TypeScript SDK that unifies USDT transfers across Ethereum, BNB Smart Chain, and TRON networks. One interface, three chains, zero complexity.

🎯 Why flash-usdt-sender?

• Unified API: Same interface for ETH, BSC, and TRON
• Type-Safe: Full TypeScript support with comprehensive types
• Battle-Tested: Production-ready error handling and validation
• Gas Optimized: Automatic gas estimation and fee management
• Zero KYC: Pure crypto, wallet-level operations
• Optional Relayer: Gas sponsorship and advanced features

📦 Installation

npm install flash-usdt-sender

Or with yarn:

yarn add flash-usdt-sender

🚀 Quick Start

import FlashUSDT from 'flash-usdt-sender';

// Initialize SDK
const flash = new FlashUSDT();

// Send USDT on Ethereum
const result = await flash.send({
  chain: 'ethereum',
  fromPrivateKey: 'YOUR_PRIVATE_KEY',
  to: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb',
  amount: '100.5',
});

console.log(`Transaction: ${result.explorerUrl}`);

📚 Usage Examples

Send USDT on Different Chains

Ethereum

const result = await flash.send({
  chain: 'ethereum',
  fromPrivateKey: process.env.PRIVATE_KEY,
  to: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb',
  amount: '50.0',
});

BNB Smart Chain

const result = await flash.send({
  chain: 'bsc',
  fromPrivateKey: process.env.PRIVATE_KEY,
  to: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb',
  amount: '50.0',
});

TRON

const result = await flash.send({
  chain: 'tron',
  fromPrivateKey: process.env.PRIVATE_KEY,
  to: 'TN3W4H6rK2ce4vX9YnFQHwKENnHjoxb3m9',
  amount: '50.0',
});

Check Balance

const balance = await flash.getBalance({
  chain: 'ethereum',
  address: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb',
});

console.log(`USDT Balance: ${balance.balance}`);

Estimate Gas (EVM Chains)

const estimate = await flash.estimateGas(
  'ethereum',
  '0xYourAddress',
  '0xRecipientAddress',
  '100.0'
);

console.log(`Estimated gas: ${estimate.estimatedCost} ETH`);

Custom RPC Endpoints

const flash = new FlashUSDT({
  rpcUrls: {
    ethereum: 'https://your-eth-rpc.com',
    bsc: 'https://your-bsc-rpc.com',
    tron: 'https://your-tron-rpc.com',
  },
});

With Debug Logging

const flash = new FlashUSDT({
  debug: true, // Enable console logging
});

With Relayer (Coming Soon)

const flash = new FlashUSDT({
  apiKey: 'your-api-key',
  relayerUrl: 'https://api.flashusdtsender.xyz',
});

// Gas-sponsored transfer
const result = await flash.send({
  chain: 'ethereum',
  to: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb',
  amount: '100.0',
  useRelayer: true, // No private key needed with relayer
});

🔑 API Reference

Constructor

new FlashUSDT(config?: FlashUSDTConfig)

Config Options:

| Option | Type | Description | |--------|------|-------------| | apiKey | string | Optional API key for relayer service | | relayerUrl | string | Optional relayer endpoint URL | | rpcUrls | object | Custom RPC endpoints for chains | | debug | boolean | Enable debug logging |

Methods

send(request: TransferRequest): Promise<TransactionResult>

Send USDT on specified chain.

Parameters:

{
  chain: 'ethereum' | 'bsc' | 'tron',
  fromPrivateKey: string,        // Sender's private key
  to: string,                    // Recipient address
  amount: string,                // Amount in USDT (e.g., "100.5")
  gasPrice?: string,             // Optional gas price override (Gwei)
  useRelayer?: boolean,          // Use relayer for gas sponsorship
}

Returns:

{
  txHash: string,                // Transaction hash
  chain: ChainType,              // Chain name
  status: 'pending' | 'confirmed' | 'failed',
  explorerUrl: string,           // Block explorer URL
  gasUsed?: string,              // Gas used (if available)
  blockNumber?: number,          // Block number (if confirmed)
}

getBalance(request: BalanceRequest): Promise<BalanceResult>

Get USDT balance on specified chain.

Parameters:

{
  chain: 'ethereum' | 'bsc' | 'tron',
  address: string,               // Address to check
}

Returns:

{
  chain: ChainType,
  address: string,
  balance: string,               // Human-readable balance
  rawBalance: string,            // Raw balance in smallest unit
}

estimateGas(chain, fromAddress, toAddress, amount): Promise<GasEstimate>

Estimate gas for transfer (EVM chains only).

🛡️ Security Best Practices

⚠️ Private Key Safety

NEVER hardcode private keys in your source code. Always use environment variables:

// ✅ GOOD
const result = await flash.send({
  chain: 'ethereum',
  fromPrivateKey: process.env.PRIVATE_KEY,
  to: recipientAddress,
  amount: '100',
});

// ❌ BAD - Never do this!
const result = await flash.send({
  chain: 'ethereum',
  fromPrivateKey: '0x1234567890abcdef...', // Exposed!
  to: recipientAddress,
  amount: '100',
});

Recommended Approaches

1. Environment Variables (Development)

# .env file
PRIVATE_KEY=your_private_key_here

2. Secure Vaults (Production)

• AWS Secrets Manager
• HashiCorp Vault
• Azure Key Vault

3. Hardware Wallets (Coming Soon)

• Ledger integration
• Trezor support

🔧 Error Handling

The SDK provides typed errors for precise error handling:

import FlashUSDT, {
  InsufficientBalanceError,
  NetworkError,
  ValidationError,
  TransactionFailedError,
} from 'flash-usdt-sender';

try {
  const result = await flash.send({...});
} catch (error) {
  if (error instanceof InsufficientBalanceError) {
    console.error('Insufficient balance:', error.details);
  } else if (error instanceof NetworkError) {
    console.error('Network issue:', error.message);
  } else if (error instanceof ValidationError) {
    console.error('Invalid input:', error.message);
  }
}

🌐 Supported Chains

| Chain | USDT Contract | Decimals | Native Token | |-------|---------------|----------|--------------| | Ethereum | 0xdAC17F958D2ee523a2206206994597C13D831ec7 | 6 | ETH | | BNB Chain | 0x55d398326f99059fF775485246999027B3197955 | 18 | BNB | | TRON | TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t | 6 | TRX |

📊 Chain Comparison

| Feature | Ethereum | BSC | TRON | |---------|----------|-----|------| | Avg. Confirmation | 15s | 3s | 3s | | Typical Gas Cost | ~$5-20 | ~$0.20 | ~$1-3 | | Transaction Speed | Medium | Fast | Fast | | Gas Model | Gas (Gwei) | Gas (Gwei) | Energy/Bandwidth |

🛣️ Roadmap

v0.1.0 (Current)

• ✅ Ethereum, BSC, TRON support
• ✅ Balance checking
• ✅ Gas estimation
• ✅ Full TypeScript types
• ✅ Error handling

v0.2.0 (Coming Soon)

• 🔄 Relayer integration
• 🔄 Gas sponsorship
• 🔄 Transaction webhooks
• 🔄 Batch transfers

v0.3.0 (Future)

• 📋 Hardware wallet support
• 📋 Meta-transactions
• 📋 Swap routing
• 📋 React Native support

🤝 Contributing

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

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

📄 License

MIT © Likhon Sheikh

🔗 Links

• NPM Package: https://www.npmjs.com/package/flash-usdt-sender
• Website: https://flashusdtsender.xyz
• GitHub: https://github.com/likhonsdev/flash-usdt-sender
• Documentation: https://flashusdtsender.xyz/docs
• Credits: CREDITS.md

💬 Support

• GitHub Issues: Report a bug
• Twitter: @likhonsdev

⚖️ Disclaimer

This SDK handles cryptocurrency transactions. Always test thoroughly on testnets before using in production. The authors are not responsible for any losses incurred through the use of this software.

👨‍💻 Built By

Developed by Likhon Sheikh 🔥

Community & Support:

• 💬 RecentCoders - Developer Community
• 🛠️ ScriptersShop - Development Services

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