Introduction
Below is a high-level, preliminary design for the BitVM-based trustless Bitcoin bridge. We offer customizable implementations tailored to meet the unique needs of each partner.
Last updated
Below is a high-level, preliminary design for the BitVM-based trustless Bitcoin bridge. We offer customizable implementations tailored to meet the unique needs of each partner.
Last updated
Our trustless Bitcoin bridge provides secure, permissionless transfers of BTC between Bitcoin and sidechains. It ensures:
Locked BTC Safety: User's BTC remains secure, without unilateral control by any entity.
Trustless PEG-IN: Bitcoin to sidechain transfers are fully permissionless.
Trustless PEG-OUT: Sidechain to Bitcoin transfers maintain the same security and trustlessness.Comment.
Traditional Approach: A committee controls your BTC, meaning they could spend it without your consent.
Our Solution: BTC is co-controlled by the user and the committee, requiring both signatures, powered by pre-signed transactions with BitVM2 functionality. This setup prevents the committee from spending BTC without user authorization.
To receive wrapped BTC on the sidechain, our system verifies transactions through a Bitcoin light client to ensure validity, preventing issues like:
Incorrect Minting: The Mint contract checks the validity of transactions on Bitcoin, ensuring that only authentic BTC transactions allow minting on the sidechain.
Relayer Issues: Users can directly submit valid data for minting if relayers are unavailable. Security is maintained by a slashing mechanism, with decentralized or permissionless relayers depending on the chain.
General Mode: Users initiate BTC transfers back to Bitcoin. The system verifies transactions for legitimacy, preventing fraudulent claims by operators through challenge periods with zero-knowledge proof (ZKP) verifications.
Forced Exit Mode: If the bridge or operator is down, users can withdraw BTC directly, with protections in place to penalize invalid claims.
Locked BTC: Secured with multisignature authorization.
PEG-IN: Trust-minimized with light client verification, ensuring permissionless operations.
PEG-OUT: Fully trustless and permissionless, with user-centric protections in place.
To reduce transaction times, our ZKP verification layer ensures prompt and final verification, aiming to reduce the current 7-day challenge period to a few hours. We are also working to support variable BTC amounts with a new liquidity provider design to increase bridge flexibility.
