Unlocking Trustless Bridges: BitVMX Goes Open Source
This article was originally published in Rootstock Labs’s webpage and it’s being included on BitVMX’s site. Fairgate and Rootstock Labs are the two founding sponsors of the BitVMX project.
BitVMX unlocks a whole host of new use cases for Bitcoin including the creation of new Bitcoin L2 light clients, zero-knowledge contingent payments, and autonomous bug bounty programs.
UNION, on the other hand, has been designed to be one of the world’s most trust-minimized and permissionless bridges between Bitcoin and the Rootstock blockchain. It will use BitVMX’s dispute-resolution model to enable BTC to move seamlessly between both ecosystems. By locking BTC within Bitcoin and releasing equal RBTC on Rootstock, users can then use their Bitcoin to interact with decentralized applications (DeFi apps, NFTs, etc.) on Rootstock, all while maintaining the trustless and decentralized principles that Bitcoin was founded on.
The architecture for the UNION bridge was unveiled on stage during Bitcoin Amsterdam 2024 by RootstockLabs’s Chief Scientist and Fairgate Co-founder Sergio Lerner, who also announced that the BitVMX code would be open-sourced as a gift to the Bitcoin community enabling any project or developer to use it to build better bridges to Bitcoin or harness it for a range of other projects. This move emphasizes the ongoing commitment from developers at Rootstock to keep the sidechain decentralized and permissionless, following the principles that Bitcoin was built.
When speaking about the open-sourcing of the BitVMX proving system, Sergio stated “BitVMX is a secure, extensible, and now open-source framework for disputable computing on Bitcoin. BitVMX represents the most efficient and cheap variant of the BitVM family of protocols.
BitVMX can be used to verify complex smart contracts on Bitcoin, such as bridges, rollup settlements, or multi-party state channels, and writing them in secure languages like Rust.”
In addition to the announcement of UNION and the open-sourcing of the BitVMX codebase, RootstockLabs, and Fairgate Labs also announced the launch of a proving system for BitVMX which will also be open-sourced. The proving system includes a RISC-V emulator generating execution traces, a Bitcoin script generator translating RISC-V instructions to Bitcoin script, and a library for generating and executing a challenge-response protocol on-chain. Written in Rust and Python, this code is used to validate a zero-knowledge proof (ZK proof) for the first time on Bitcoin.
While this initial implementation of BitVMX is not yet production-ready, RootstockLabs welcomes contributions from the community to help advance its work.
