Go-OPReturn

A powerful Bitcoin CLI tool for creating and broadcasting Bitcoin transactions with OP_RETURN data using WIF private keys. Built with Go and featuring a modern, user-friendly interface.

Features

• 🚀 Easy OP_RETURN Creation - Create Bitcoin transactions with custom data payloads
• 🔐 WIF Private Key Support - Works with standard WIF keys and Electrum p2wpkh format
• 💰 Fixed 20% Fee Structure - Transparent, predictable pricing with automatic network fee calculation
• 🌐 Multi-Network Support - Works with both Bitcoin mainnet and testnet
• 📡 Real-time UTXO Management - Live UTXO validation and refresh capabilities
• 🎨 Beautiful CLI Interface - Modern, colored output with clear information display
• 🛡️ Built-in Safety Checks - Dust threshold validation and UTXO availability verification

Installation

Prerequisites

• Go 1.19 or higher
• Git

Build from Source

# Clone the repository
git clone https://github.com/slashbinslashnoname/go-opreturn.git
cd go-opreturn

# Build the binary
make build

# Or build manually
go build -o go-opreturn main.go

Download Pre-built Binary

Pre-built binaries are available for various platforms in the releases section.

Usage

Basic Usage

# Run with default settings (mainnet)
./go-opreturn

# Specify network
./go-opreturn --network testnet

Command Line Options

./go-opreturn [flags]

Flags:
  -n, --network string   Bitcoin network (mainnet or testnet) (default "mainnet")
  -h, --help            help for opreturner

Interactive Workflow

1. Select Network - Choose between mainnet or testnet
2. Enter WIF Key - Provide your WIF private key (supports Electrum p2wpkh: prefix)
3. Select UTXO - Choose from available unspent transaction outputs
4. Enter OP_RETURN Data - Specify your custom data (max 80 bytes)
5. Review & Confirm - Check transaction details before creation
6. Get Transaction Hex - Receive the raw transaction for broadcasting

Fee Structure

Go-OPReturn uses a fixed 20% fee structure:

• Service Fee: 20% of the selected UTXO value
• Network Fee: Automatically calculated based on current mempool.space rates
• Recipient Amount: Service fee minus network fee
• Change: Remaining amount returned to your address

Example

For a 10,000 satoshi UTXO:

• Service Fee: 2,000 satoshis (20%)
• Network Fee: ~500 satoshis (varies by network conditions)
• Recipient Amount: 1,500 satoshis
• Change: 7,500 satoshis

Supported Networks

• Mainnet - Production Bitcoin network
• Testnet - Bitcoin test network for development and testing

API Dependencies

Go-OPReturn uses the following external APIs:

• mempool.space - UTXO data and fee rate information
• Mainnet: https://mempool.space/api
• Testnet: https://mempool.space/testnet/api

Security Features

• UTXO Validation - Multiple validation checks to ensure UTXO availability
• Dust Threshold Protection - Prevents creation of dust outputs
• Live Status Checking - Real-time verification before transaction creation
• Network Fee Optimization - Dynamic fee calculation based on current network conditions

Technical Details

OP_RETURN Implementation

• Maximum Data Size: 80 bytes
• Output Type: Null data script (OP_RETURN)
• Transaction Structure: 1 input, 3 outputs (recipient, OP_RETURN, change)

Supported Address Types

• SegWit (P2WPKH) - Native SegWit addresses (bc1...)
• Legacy WIF Keys - Standard WIF private key format
• Electrum Format - p2wpkh: prefixed keys

Transaction Signing

• SegWit Support - Native SegWit transaction signing
• Witness Data - Proper witness structure for SegWit transactions
• Script Signature - Empty scriptSig for SegWit inputs

Development

Project Structure

go-opreturn/
├── main.go          # Main application code
├── go.mod           # Go module dependencies
├── go.sum           # Go module checksums
├── Makefile         # Build and development tasks
└── README.md        # This file

Dependencies

• btcsuite/btcd - Bitcoin protocol implementation
• btcsuite/btcutil - Bitcoin utility functions
• charmbracelet/lipgloss - Terminal styling
• manifoldco/promptui - Interactive prompts
• spf13/cobra - CLI framework

Building

# Build for current platform
make build

# Build for all platforms
make build-all

# Clean build artifacts
make clean

# Run tests
make test

Troubleshooting

Common Issues

1. "No UTXOs available"

   • Check if the address has confirmed transactions
   • Ensure you're using the correct network (mainnet/testnet)

2. "UTXO validation failed"

   • The selected UTXO may have been spent
   • Use the refresh option to get updated UTXO list

3. "Dust threshold" errors

   • UTXO value is too small (minimum 1000 satoshis)
   • Select a larger UTXO or wait for more confirmations

4. "WIF key network mismatch"

   • Ensure your WIF key matches the selected network
   • Use testnet keys for testnet, mainnet keys for mainnet

Debug Information

The tool provides extensive debug output including:

• UTXO selection details
• Transaction structure information
• Fee calculations
• Validation steps

Contributing

Contributions are welcome! Please feel free to submit pull requests or open issues for bugs and feature requests.

Development Guidelines

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests if applicable
5. Submit a pull request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Disclaimer

⚠️ Important Security Notice

• This tool handles private keys - use with caution
• Always test with small amounts first
• Keep your private keys secure and never share them
• The authors are not responsible for any loss of funds
• Use at your own risk

Support

If you need help or have questions:

• Open an issue on GitHub
• Check the troubleshooting section above
• Review the debug output for detailed information

Roadmap

• Support for multiple UTXO inputs
• Batch transaction creation
• Custom fee rate selection
• Transaction template saving
• Integration with more Bitcoin APIs
• Web interface option

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Made with ❤️ for the Bitcoin community