Introduction to ZeusLayer

Introduction to ZeusLayer

ZeusLayer is a cross-chain layer that enables interoperability between Bitcoin and programmable blockchains like Solana. The architecture is designed to provide security, scalability, and a seamless user experience across both chains.

Lifecycle of Interactions

Check the live Interaction data on ZeusScan

Deposit Flow

Withdrawal Flow

Core Components

• ZPL (Zeus Program Library): A set of Solana programs that run on-chain, including:

  • BitcoinSPV: Verifies Bitcoin transactions using simplified payment verification
  • TwoWayPeg: Manages the pegging and unpegging of assets between chains
  • LiquidityManagement: Handles asset storage, retrieval, and liquidity pools

• ZeusNode: Off-chain components that handle:

  • Transaction Signing: Securely sign cross-chain transactions
  • Relaying: Propagating transactions between Bitcoin and Solana
  • Monitoring: Tracking transaction status and system health

Layer Roles

• Operator:
  • Manages the system operations
  • Monitors deposits and withdrawal requests
  • Proposes transactions for guardian approval
• Guardian (Signing Entity):
  • Provides security through multi-signature
  • Validates and approves cross-chain operations
  • Manages key recovery and emergency procedures

Reserves

There are two types of reserves to manage Bitcoin assets:

HotReserve (Bitcoin)

HotReserve is a temporary storage for user deposits before they are moved to ColdReserve:

• Short-term storage for user deposits
• Provides quick access for frequent operations
• Uses Taproot addresses with user-specific script paths

ColdReserve (Bitcoin)

ColdReserve is a long-term secure storage for pooled Bitcoin:

• Long-term, secure storage for Bitcoin
• Higher security with multi-signature protection
• Uses Taproot addresses with time-locked script paths

zBTC Vault

zBTC is a wrapped representation of Bitcoin on Solana:

• SPL Token: Follows the Solana Program Library token standard
• 1:1 Backing: Each zBTC is backed by an equivalent amount of BTC in reserves
• Programmable: Can be used in Solana DeFi applications

zBTC vault manages the issuance and redemption of zBTC tokens:

• Token Minting: Creates new zBTC when BTC is deposited
• Token Burning: Burns zBTC when BTC is withdrawn
• Balance Tracking: Ensures the system maintains proper reserves

Core Concepts

Bitcion Taproot

ZeusLayer leverages Bitcoin’s Taproot technology (BIP 341), which provides enhanced privacy and flexibility:

• Key-path Spend: Uses the Guardian’s internal X-only public key for standard operations
  • More efficient and private spending path
  • Lower transaction fees
  • Indistinguishable from regular Bitcoin transactions
• Script-path Spend: Uses the User’s X-only public key with time-locked scripts for recovery
  • Enables complex spending conditions
  • Provides backup recovery mechanisms
  • Allows for time-locked security features

Simplified Payment Verification (SPV)

We deploy a BitcoinSPV program on Solana that verifies Bitcoin transactions without requiring a full Bitcoin node:

• Block Headers: Validates the Bitcoin blockchain structure
• Merkle Proofs: Confirms transaction inclusion in blocks
• Transaction Parsing: Extracts relevant data from Bitcoin transactions