BitVMX
BitVMX is a cutting-edge framework designed to bring universal computation capabilities to Bitcoin through disputable computation models.
Here, you'll find an overview of its core features and the innovative mechanics that make it a game-changer for scalability and programmability on Bitcoin.
For a deeper dive into BitVMX's full potential, visit the official site at bitvmx.org.
Background
In 2023 Robin Linus discovered BitVM, a clever mechanism to use the current Bitcoin scripting system to verify arbitrary conditions and restrict bitcoin spending based on those conditions, assuming miners cannot censor transactions.
The proposal was soon expanded from the two-party setting to N-party protocols. While BitVM (a.k.a. tapleaf circuits) was only of theoretical interest, soon afterwards, he proposed two improvements that make it practical: BitVM1 and BitVM2. We pushed the research forward with BitVMX, improving both pre-computation, on-chain vbytes consumed, round complexity and design simplicity
What is BitVMX?
BitVMX is a cutting-edge framework designed to optimistically execute arbitrary programs on Bitcoin, leveraging the N-party disputable computation paradigm introduced by BitVM.
With its foundation in secure, extensible, and open-source principles, BitVMX paves the way for running any CPU on Bitcoin, particularly focusing on a fully-compliant RISC-V processor programmable with standard compilation toolchains.
| Protocol | Preprocessing Time | Storage | Rounds | Transaction virtual bytes |
| BitVM | Weeks | Terabytes | ~ 50 | ~ 6 Megabytes |
| BitVM CPU | Days | Gigabytes | ~ 38 | ~280 Kilobytes |
| BitVM2 | Minutes | Megabytes | 1 | ~ Tens of Megabytes |
| BitVMX (*) | Milliseconds | Kilobytes | ~ 34 | ~160 Kilobytes |
For the comparison we use a BitVMX protocol using 4-way search, and a hashing function split into 8 challengeable sub-functions.
From Two-Party to N-Party Computation
The BitVMX protocol builds on the two-party model of BitVM and extends it to support N-party computation
Key Features:
- Versatility: Enables the development of blockchain bridges, aggregator oracles, and SNARK/STARK verifiers.
- Future-Proof: Unlocks advanced use cases like ZK-rollups and Zero Knowledge Contingent Payments (e.g., autonomous bug bounties).
- Collaboration-Driven: Developed and maintained by Fairgate Labs with the Open Source community, with Rootstock Labs as the main and founding sponsor.