Avail introduces OpEVM for sovereign EVM-compatible Optimistic Rollups

Avail — a modular blockchain solution for data availability spun out from Polygon — has introduced OpEVM, a prototype software development kit enabling developers to create sovereign EVM-compatible Optimistic Rollups on testnet. 

Optimistic Rollups are a Layer 2 scaling solution for Ethereum that aim to increase the transaction throughput and reduce fees while still maintaining the security and decentralization of the main chain. Multiple transactions are aggregated into a single batch before submitting them to Layer 1, with fraud proofs used to verify the validity of the batches.

How OpEVM works

Built in collaboration with DeFi hub Equilibrium, OpEVM follows the introduction of Avail’s Kate testnet last month. OpEVM separates execution and data availability layers, enabling an execution layer to be built on top of Avail’s modular base layer. This means that developers can run existing EVM contracts on OpEVM to build self-resolving rollups without relying on an execution-capable base layer like Ethereum for data availability, according to a statement.

“It also has support for a decentralized sequencer set and watchtowers so that there’s no single point of failure, making OpEVM more secure and censorship-resistant than traditional rollups with centralized sequencers or permissioned watchtowers,” Avail added.

More specifically, in OpEVM’s infrastructure, the Bootstrap Sequencer initiates the system and generates the genesis block. The Sequencer manages transactions and incorporates them into the Avail blockchain, while the WatchTower examines the blocks for signs of fraud. A staking feature enables user participation in the network's consensus and its Fraudproof Testing feature checks disputes.

Taking on traditional rollup designs

Traditional rollups use enshrined bridges to resolve disputes on the main chain — which can be slow and expensive, limiting their scalability and efficiency, Avail said. Instead, OpEVM uses fraud proofs within the rollup to determine the validity of transactions — making them more independent and cost-effective without relying on smart contract dispute resolution used in conventional rollup designs, Avail added.

OpEVM completely relies on node operators to determine the state of the chain, “making it completely sovereign, while still inheriting the security of the base layer,” Avail said. By leveraging Avail's data availability layer, developers can create rollups without requiring a separate validator set, offering scalability and efficiency without worrying about infrastructure support, it added.

“This prototype proves the feasibility of decoupling the data availability layer from execution,” Avail co-founder Prabal Banerjee said. “Our objective is not to compete with existing optimistic protocols; rather, we want to show that optimistic rollups with a decentralized sequencer set and permissionless watchtower can be built along with working fraud proofs.”  

Avail said its ultimate goal is to develop a zk/validity proof construct, further unlocking the potential of rollups on modular base layers. 

Avail’s phase 2 Kate testnet followed its initial testnet launch in June 2022 on its roadmap toward mainnet.