Rollup BSN Contracts

Bitcoin-secured finality for rollups through Babylon's Bitcoin staking protocol.

This repository contains the finality contract that enables Ethereum Rollups to become Bitcoin Supercharged Networks (BSNs) by inheriting Bitcoin's economic security through Babylon's staking infrastructure.

What is Rollup BSN?

Bitcoin Supercharged Networks (BSNs) are blockchain networks that leverage Bitcoin's economic security through Babylon's Bitcoin staking protocol. BSNs enhance their security by tapping into Bitcoin's massive economic security, where Bitcoin stakers delegate their BTC to provide cryptographic attestations for network finality.

How It Works

1. Deploy Contract - Deploy this finality contract on Babylon Genesis chain
2. Register BSN - Register your rollup as a Bitcoin Supercharged Network
3. BTC Delegation - Bitcoin stakers delegate their BTC to finality providers
4. Block Finalization - Finality providers sign rollup blocks and submit signatures to the contract
5. Cross-Chain Security - Your rollup inherits Bitcoin's economic security through Babylon's infrastructure

The finality contract acts as the bridge between your rollup and Babylon's Bitcoin staking protocol, maintaining an immutable record of block finalization and ensuring finality providers remain honest through economic incentives.

Note: To read finalized data from contracts on Babylon Genesis, you should use an already built off-chain service or build your own. We have a proof-of-concept available at rollup-finality-gadget.

Learn More: To understand how finality providers work and how to become one, visit the finality-provider repository.

Security Through Cryptography

The system uses EOTS (Extractable One-Time Signatures) to ensure finality provider honesty:

• Public Randomness Commitment - Finality providers pre-commit to randomness values they'll use for signing
• Block Finality Signatures - Finality providers sign rollup block data using their private keys
• One-Time Signatures - Each signature uses unique randomness and can only be used once safely
• Automatic Slashing - If a provider signs two different blocks at the same height (double-signing), the contract automatically extracts their private key and triggers slashing

Repository Structure

• contracts/finality/ - Core finality contract implementing BSN integration
• docs/ - Comprehensive technical specifications and guides
• e2e/ - End-to-end integration tests
• scripts/ - Development and deployment utilities

Quick Start

Prerequisites

# Install dependencies
cargo install cargo-run-script

Build & Test

# Build the contract
cargo build

# Run tests
cargo test --lib

# Build optimized version for deployment
cargo run-script optimize

Deploy to Babylon

1. Upload Contract: Deploy WASM bytecode to Babylon Genesis
2. Instantiate: Configure your BSN parameters
3. Register BSN: Register with Babylon's consumer registry
4. Go Live: Start accepting finality signatures from Finality Providers

See our Contract Management Guide for detailed deployment instructions.

Development Commands

# Linting & formatting
cargo run-script lint

# Integration tests (requires optimized build)
cargo run-script integration

# End-to-end tests
cargo run-script e2e

# Generate contract schema
cargo run-script schema

Contributing

We welcome contributions! This project follows the same guidelines as the Babylon node repository.

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Need Help? Check our documentation or open an issue for support.

Learn More: Visit Babylon Labs to understand the broader Bitcoin staking ecosystem.