New Paper Envisions Design That Can Push Bitcoin Toward Programmability

• Robin Linus introduced the second iteration of his BitVM breakthrough in a new whitepaper titled “BitVM2: Bridging Bitcoin to Second Layers.”
• BitVM2 can possibly bring permissionless rollup technology to Bitcoin without altering the Bitcoin code.

Robin Linus authored BitVM2 whitepaper is taking the Bitcoin community by storm, thanks to its comprehensive explanation of a layer 2 rollup solution making dapp deployment possible on Bitcoin. This paper follows Linus’ previous paper detailing BitVM, which led to a flurry of rollup solutions developed to make Bitcoin programming possible. At least 83 rollup-related solutions built by developers across the board exist thus far.

The current iteration was co-authored by Lukas Aumayr, Andrea Pelosi, Zeta Avarikioti, Matteo Maffe, and Alexei Zamyatin alongside Linus. It depicts an improved version of rollup functioning, which can execute programs within Bitcoin transactions using enhanced cryptography. That allows dividing programs into sub-programs to make improvements possible and push the limitations of the predecessor, BitVM.

BitVM2 will use optimistic rollup and zk-SNARK technologies for transaction verification purposes on layer-2s. The whitepaper reads, “At its core, BitVM2 leverages optimistic computation, assuming operators are honest unless proven otherwise by challengers through fraud proofs, and SNARK proof verification scripts, which are split into sub-programs that are executed within Bitcoin transactions. As a result, BitVM2 ensures program correctness with just three on-chain transactions.”

A Permissionless Rollup Solution

Furthermore, transaction verifications in this model are permissionless and open to anybody wanting to challenge a layer-2 transaction they deem to go against Bitcoin’s rules. Previously, a selected set of operators would carry out this process, in line with how rollup solutions across the blockchain ecosystem work, including those operating as Ethereum layer-2s. The verification can occur over three Bitcoin transactions using the BitVM2 design compared to the 70 transactions that BitVM can take at times.

BitVM2 also envisions a bridge connecting layer-2 rollup solutions with Bitcoin, ensuring bitcoin transfers between the main chain and the rollups, and vice versa, securely. This new iteration will bring layer-2s as add-ons to the existing Bitcoin network without needing Bitcoin core developers to change any code to accommodate the solutions.