Polygon to Ethereum Bridge Test part 1

This project implements a bridge to transfer tokens from Polygon (Layer 2) back to Ethereum (Layer 1) using the Polygon PoS Bridge mechanism.

Features

• Withdraw (burn) tokens on Polygon network
• Wait for checkpoint completion
• Submit proof to unlock tokens on Ethereum

Prerequisites

• Python 3.13 or higher
• Ethereum wallet with private key
• Infura account (or other Ethereum RPC provider)
• Sufficient tokens on Polygon network
• Sufficient MATIC for gas fees on Polygon
• Sufficient ETH for gas fees on Ethereum

Setup

1. Clone the repository

2. Install dependencies using uv:

uv venv
source .venv/bin/activate
uv pip install -e .

3. Copy .env.example to .env and configure:

cp .env.example .env

4. Set the following environment variables in .env:

• ETH_RPC_URL: Your Ethereum RPC endpoint
• POLYGON_RPC_URL: Polygon RPC endpoint
• PRIVATE_KEY: Your wallet's private key (without 0x prefix)
• CHILD_TOKEN_ADDRESS: Token contract address on Polygon

Dependencies

• python-dotenv >= 1.0.1
• requests >= 2.32.3
• web3 >= 7.8.0

Usage

Run the bridge script:

python bridge_to_ethereum.py

The script will:

1. Withdraw tokens on Polygon
2. Wait for checkpoint (approximately 30 minutes)
3. Submit proof to unlock tokens on Ethereum

Important Notes

• The bridge process takes approximately 30+ minutes due to checkpoint requirements
• Ensure sufficient gas fees on both networks
• Keep your private key secure and never share it
• Test with small amounts first

Network Addresses

• Root Chain Manager (Ethereum): 0x86E4Dc95c7FBdBf52e33D563BbDB00823894c287
• Child Token (Polygon): Set in environment variables