* BOB has introduced hybrid ZK proofs that replace traditional bisection and resolve disputes in a single transaction, cutting costs and boosting speed.
* The system enables instant withdrawals on Ethereum via on-demand validity proofs, or keeps fees low by operating with optimistic proofs.
* Verification on Bitcoin through BitVM unlocks native bridges and smart contracts, with ZK proofs that can be audited directly on the base layer.
BOB has just deployed a hybrid ZK proof system that merges the best of optimistic and validity rollups. Through OP Kailua, an extension of the OP Stack, the network uses zero-knowledge-based fraud proofs to settle disputes in a single transaction. This reduces costs and speeds up finality without compromising security.
The use of ZK fraud proofs replaces the traditional bisection process used by optimistic rollups. With a deposit of just 0.5 ETH and under $50 in fees, anyone can issue a challenge. The proof is generated using Boundless and RISC Zero and is resolved within minutes. When speed is critical, an on-demand validity proof can be triggered for instant withdrawals on Ethereum — no need to wait seven days.
This approach reduces costs and simplifies liquidity management. Autodepositing USDC or SOL into yield protocols no longer hinders quick fund exits. If no validity proof is requested, the network runs with low fees and confirms transactions optimistically. When integrity matters, users can simply pay for ZK validation to gain full certainty.
A public dashboard brings transparency to every chain proposal, challenge, and outcome. All activity is logged in real time, making it easy to track balances, flows, and proof results. These records let developers, validators, and users audit the network with no barriers.
BitVM: BOB Paves Bitcoin’s Path to DeFi
With OP Kailua, BOB has reached Stage 0 on the L2BEAT platform and is moving toward Stages 1 and 2, which require external security councils and time delays for code upgrades. So far, only two networks have reached Stage 2, but BOB already has the proof infrastructure to scale quickly.
The most disruptive leap comes with BitVM. ZK proofs can now be verified directly on the Bitcoin blockchain. This unlocks native bridges and smart contracts secured by the most robust network in the world. Thanks to this integration, BOB aims to become a gateway to the Bitcoin DeFi ecosystem, offering users and institutions the ability to move BTC with strong cryptographic guarantees.
A livestream featuring the teams from BOB, RISC Zero, Boundless, Conduit, and L2BEAT is scheduled for Thursday, July 31, to break down the technical details of this upgrade
