Deploying a Vyper Smart Contract to Rootstock Testnet using Python

Rootstock is a layer 2 solution that combines the security of Bitcoin's proof of work with Ethereum's smart contract capabilities. The platform is open-source, EVM-compatible, and secured by over 60% of Bitcoin’s hashing power, offering unique advantages for developers.

This guide demonstrates how to deploy smart contracts written in Vyper to the Rootstock testnet using Python and Web3.py.

• Bitcoin Compatibility: Deploy smart contracts while leveraging Bitcoin's security and network effects
• EVM Compatibility: Use familiar Ethereum tools and practices while building on Bitcoin
• Lower Fees: Benefit from low transaction fees on Rootstock
• Scalability: Handle a higher volume of transactions without congestion

We'll walk through creating a simple Vyper contract and deploying it to the Rootstock testnet, covering everything from environment setup to handling Rootstock-specific network configurations.

Whether you're an experienced Ethereum developer looking to expand to Bitcoin-based smart contracts, or just starting your blockchain journey, this guide will help you get up and running with Vyper Contracts on Rootstock.

Prerequisites

• uv
  • To confirm installation, run uv --version, it should return a version number.
• git
  • To confirm installation, run git --version, it should return a version number.
  • Helpful shortcut:

# For bash
echo "source $HOME/.bashrc >> $HOME/.bash_profile"

# For zsh
echo "source $HOME/.zshenv >> $HOME/.zprofile"

Installing Python

Installing Python on Windows

1. Visit the Python downloads page
2. Click on the "Download Python 3.12.x" button
3. Run the downloaded installer
4. Important: Check the box that says "Add Python 3.12 to PATH"
5. Click "Install Now"
6. Once installation is complete, open Command Prompt and verify the installation:

python --version

Installing Python on Mac

1. Visit python.org
2. Under Downloads, go to macOS and download the latest Python 3.12 release
3. Click the link for the Python 3.12.x macOS 64-bit universal2 installer
4. Open the installer file and agree to the license agreement
5. Click Continue, then Install
6. Once complete, open Terminal and verify the installation:

python3 --version
# or
python --version

Installing Python on Linux

Most Linux distributions come with Python pre-installed. To verify, open Terminal and run:

python3 --version

If Python is not installed, you can install it using your distribution's package manager:

For Ubuntu/Debian:

sudo apt update
sudo apt install python3

For Fedora:

sudo dnf install python3

For Arch Linux:

sudo pacman -S python

Installation

git clone https://github.com/EdwinLiavaa/Web3py-Vyper-RootStock.git
cd Web3py-Vyper-RootStock

Syncing uv

uv sync is a fast package management command that downloads and installs your project's Python dependencies while creating a lockfile for reproducible installations.

uv sync

pip/python

The pip/python section creates a virtual environment (python -m venv ./venv), activates it (source ./venv/bin/activate), and installs the project dependencies from requirements.txt (pip install -r requirements.txt).

python -m venv ./venv
source ./venv/bin/activate
pip install -r requirements.txt

Quickstart

Both uv run hello.py and python hello.py will run the script and output "Hello from web3py-Vyper-RootStock!", with UV being preferred for faster, modern projects and pip for traditional Python setups.

uv run hello.py # for UV
# or
python hello.py # for pip/python

Setup Environment

To set up our Python environment and install the necessary packages, we will do the following:

# Create and activate virtual environment
python3 -m venv .venv
source .venv/bin/activate

# Install required packages
pip install python-dotenv web3 vyper

Configuration

Create a .env file in the project root and specify your custom configuration:

RPC_URL="https://rpc.testnet.rootstock.io/[YOUR-API-KEY]"
PRIVATE_KEY="your-private-key"  # Never commit your real private key!
MY_ADDRESS="your-wallet-address"

THIS IS ONLY FOR TESTING - TYPICALLY YOU SHOULD NEVER SHARE YOUR PRIVATE KEY.

Get Testnet RBTC

Before deploying, you'll need some testnet RBTC:

1. Go to the Rootstock faucet: https://faucet.rootstock.io/
2. Enter your wallet address
3. Complete the captcha and request funds
4. Wait a few minutes for the transaction to be confirmed

The Smart Contract

Here's a simple Vyper contract (favorites.vy):

# @version ^0.3.7

favorite_number: public(uint256)
owner: public(address)

@external
def __init__():
    self.owner = msg.sender
    self.favorite_number = 0

@external
def store(new_number: uint256):
    self.favorite_number = new_number

Deployment Script

Here's a Python script to deploy the contract (deploy_favorites_unsafe.py):

from web3 import Web3
from dotenv import load_dotenv
from vyper import compile_code
import os

load_dotenv()

RPC_URL = os.getenv("RPC_URL")

def main():
    print("Let's read in the Vyper code and deploy it to the blockchain!")
    w3 = Web3(Web3.HTTPProvider(RPC_URL))
    with open("favorites.vy", "r") as favorites_file:
        favorites_code = favorites_file.read()
        compliation_details = compile_code(
            favorites_code, output_formats=["bytecode", "abi"]
        )

    chain_id = 31  # RSK testnet chain ID

    print("Getting environment variables...")
    my_address = os.getenv("MY_ADDRESS")
    private_key = os.getenv("PRIVATE_KEY")

    # Check balance before deployment
    balance = w3.eth.get_balance(my_address)
    balance_in_rbtc = w3.from_wei(balance, "ether")
    print(f"Account balance: {balance_in_rbtc} RBTC")

    if balance == 0:
        print("Your account has no RBTC! Please get some testnet RBTC from the faucet:")
        print("1. Go to https://faucet.rsk.co/")
        print("2. Enter your address:", my_address)
        print("3. Complete the captcha and request funds")
        print("4. Wait a few minutes for the transaction to be confirmed")
        return

    # Create the contract in Python
    favorites_contract = w3.eth.contract(
        abi=compliation_details["abi"], bytecode=compliation_details["bytecode"]
    )

    # Submit the transaction that deploys the contract
    nonce = w3.eth.get_transaction_count(my_address)

    print("Building the transaction...")
    transaction = favorites_contract.constructor().build_transaction(
        {
            "chainId": chain_id,
            "from": my_address,
            "nonce": nonce,
            "gas": 3000000,  # Higher gas limit for RSK
            "gasPrice": w3.eth.gas_price * 2,  # Double the gas price to ensure transaction goes through
        }
    )

    print("Signing transaction...")
    signed_txn = w3.eth.account.sign_transaction(transaction, private_key=private_key)
    print("Deploying contract...")
    tx_hash = w3.eth.send_raw_transaction(signed_txn.rawTransaction)
    tx_receipt = w3.eth.wait_for_transaction_receipt(tx_hash)
    print(f"Contract deployed! Address: {tx_receipt.contractAddress}")

if __name__ == "__main__":
    main()

Notable Info when Deploying on Rootstock

1. Chain ID: RSK testnet uses chain ID 31
2. Gas Settings:
   • Use a higher gas limit (3,000,000) for Rootstock
   • We double the gas price to ensure the transaction goes through
3. Transaction Type:
   • Rootstock is optimized for legacy transactions, utilizing gasPrice rather than EIP-1559 parameters.

Running the Deployment

Execute the deployment script:

For Linux Users:

python deploy_favorites_unsafe.py

For Windows Users:

python3 deploy_favorites_unsafe.py

Useful Links

The boilerplate used in this project was adopted from the Cyfrin Updraft Python and Viper Starter Kit:

• Cyfrin Updraft @cyfrinupdraft