PySubnet

The easiest way to /develop/deploy/test a multi-node substrate network

🚀 What is PySubnet?

PySubnet is a beginner-friendly tool that automates the complex process of setting up multi-node Substrate blockchain networks. Whether you're a blockchain developer learning Substrate or deploying production networks, PySubnet handles all the tedious setup work for you.

✨ What PySubnet Does for You:

• 🔑 Generates all cryptographic keys for your validator authorities (AURA, BABE, GRANDPA)
• 📁 Creates proper directory structure for your network nodes
• ⚙️ Prepares a chainspec with bootnodes and validator keys
• 🔗 Sets up p2p keys (libp2p keys for bootnodes list)
• 💸 Funds starting balances for any number of accounts for you without having to manually edit chainspec files. (See example in nodes.toml)
• 🏃‍♂️ Launches your network with a single command (-r)
• 🎨 Interactive CLI with beautiful, colorful output (-i)

Crafted For:

• Blockchain Developers learning the Substrate framework with multi-node setups
• DevOps Teams for managing multiple sets of keys for separate nodes
• Rapid Prototyping of blockchain applications

📦 Installation

Option 1: Install with uv pip (Recommended)

uv pip install pysubnet
# or install it as a tool
uv tool install pysubnet

Option 2: Latest from GitHub

pip install git+https://github.com/weezy20/pysubnet.git

Option 3: Run without installing (using uvx)

uvx git+https://github.com/weezy20/pysubnet.git

💡 Tip: If you get Python header errors during installation:

• Ubuntu/Debian: sudo apt install python3-dev
• RHEL/Fedora: sudo dnf install python3-devel
• macOS: xcode-select --install

Step 2: Run PySubnet

pysubnet

That's it! PySubnet will automatically start in interactive mode and guide you through the setup.

Step 3: Choose Your Network Type

PySubnet will present you with 5 commonly used consensus options:

1. 🟢 PoA (Proof-of-Authority) - Perfect for learning and simple development
2. 🟡 PoA + ValidatorSet - PoA with sessions pallet and substrate-validator-pallet for dynamic authority management Note: To use this pallet (substrate-validator-set) it's recommended to clone it locally and add it to your runtime because as of this writing, it's dependecies seem outdated, but its functionality is unaffected
3. 🔵 BABE + GRANDPA - Production-ready consensus (like Polkadot)
4. 🟣 BABE + GRANDPA + Staking - Full production setup with economic security
5. 🔴 Development Mode - Single node for rapid development

🎮 Interactive Mode Features

When you run pysubnet, it automatically detects if you have a substrate binary and provides:

• 🎨 Beautiful CLI interface with colors and progress bars
• 🤖 Smart substrate detection - automatically switches to interactive mode if no binary found
• ❓ Helpful prompts - clear explanations for each option
• 🔧 Flexible configuration - choose exactly what you need
• 📊 Real-time feedback - see your network being built step by step

🔧 Advanced Usage

Non-Interactive Mode

# Quick setup with defaults
pysubnet --clean --run
# Or a shorter version
pysubnet -cr

# Custom binary location
pysubnet --bin ./target/release/my-node --run

# Using Docker
pysubnet --docker substrate:latest --run

# Custom chainspec
pysubnet --chainspec ./my-chainspec.json --run

Configuration File

Create advanced network configurations:

pysubnet --config ./network-config.toml --run

See docs/config.md for configuration examples.

Directory Structure

PySubnet creates organized directories:

./network/                    # Default root directory
├── pysubnet.json            # Network configuration & keys
├── chainspec.json           # Generated chainspec
├── raw_chainspec.json       # Raw chainspec for nodes
├── alice/                   # Node directories
│   ├── alice-node-private-key
│   └── chains/<chain folder based on running chainspec>/keystore/
├── bob/
└── charlie/

📊 Complete Flag Reference

🎓 Learning Resources

New to Substrate?

The first tutorial on substrate is about running a PoA node with 2 or 3 nodes. You can replicate that entire tutorial with pysubnet by running pysubnet -icr --poa --bin <your poa enabled node>.

🤝 Getting Help

• 🐛 Issues: GitHub Issues
• 💬 Discussions: GitHub Discussions

• All node data (crypto keys, Account keys, libp2p keys, node IDs) is stored in pysubnet.json.
• The script auto-generates keystores compatible with Substrate’s expected format.

💡 Tips & Best Practices

• 🧹 Always use --clean/-c when restarting development to avoid issues.
• 📝 Save your pysubnet.json - After having a proper setup, save this file for your future reference, it contains all your network keys and configuration

📈 What's New in v2.0

• 🎯 5 Consensus Options (upgraded from 2)
• 🎨 Enhanced Interactive Mode with beautiful CLI
• 🤖 Smart Binary Detection with automatic fallback
• 📦 Modular Architecture for easier customization

Made with ❤️ for the Substrate community