Scroll Tech aims to build an EVM-compatible zk-Rollup with a strong proving network. After months of exploration, we have made great technical progress. In this post, we’d like to share our progress and updates. We also present an overview of the problems to help everyone onboard.

We set the following goals.

• Scroll will build a fully EVM-compatible zk-Rollup. We will support the direct verification of a Ethereum block through one succinct proof. The basic idea is to verify the consistency and integrity of each opcode in EVM execution trace. This way, L1 smart contracts can be seamlessly migrated to Scroll. Instead of using new zk-friendly primitives, we will build reversely — we will support native EVM using customized optimizations. This brings us huge advantage to be compatible with all existing Ethereum infrastructures without any modification!

• Scroll will enable and standardize Layer-2 proof outsourcing. We have designed a robust outsource mechanism which can incentivize rollers to generate zero-knowledge proofs for us. We will standardize such scheme to fit into a broader spectrum of general off-chain computations. This will open a new proof market. Another direct influence for developers is that they can deploy complicated contracts in Scroll without considering the gas limit. A lot of new applications can be enabled off-chain with proofs committed on-chain. Our team has also built the fastest GPU and ASIC prover in the world to support this. In the long term, we plan to achieve full decentralization and reduce the influence of MEV.

• Scroll will upgrade to a new proof system. As proposed five months ago, Scroll will adopt a new hierarchical zero-knowledge proof system. The first layer will be prover efficient (customized circuit optimization and hardware efficient proving algorithm). The second layer will be verifier efficient (succinct proof and EVM-friendly verification algorithm). Compared to all existing solutions, it has potential to support program even larger than EVM and more features like privacy.

• We will elaborate more for each one in the following articles. Each bullet-point will link to an article. If the link is not there, then it means “coming soon”!

  • Introduction to zkEVM

  • More technical details of zkEVM

  • Introduction to Layer-2 proof outsourcing

  • More technical details of Layer-2 proof outsourcing

  • Introduction to proof system upgrade

  • More technical details of the trade-offs between different proof systems

Scroll Tech aims to build an EVM-compatible zk-Rollup with a strong proving network. After months of exploration, we have made great technical progress. In this post, we’d like to share our progress and updates. We also present an overview of the problems to help everyone onboard.

We set the following goals.

• Scroll will build a fully EVM-compatible zk-Rollup. We will support the direct verification of a Ethereum block through one succinct proof. The basic idea is to verify the consistency and integrity of each opcode in EVM execution trace. This way, L1 smart contracts can be seamlessly migrated to Scroll. Instead of using new zk-friendly primitives, we will build reversely — we will support native EVM using customized optimizations. This brings us huge advantage to be compatible with all existing Ethereum infrastructures without any modification!

• Scroll will enable and standardize Layer-2 proof outsourcing. We have designed a robust outsource mechanism which can incentivize rollers to generate zero-knowledge proofs for us. We will standardize such scheme to fit into a broader spectrum of general off-chain computations. This will open a new proof market. Another direct influence for developers is that they can deploy complicated contracts in Scroll without considering the gas limit. A lot of new applications can be enabled off-chain with proofs committed on-chain. Our team has also built the fastest GPU and ASIC prover in the world to support this. In the long term, we plan to achieve full decentralization and reduce the influence of MEV.

• Scroll will upgrade to a new proof system. As proposed five months ago, Scroll will adopt a new hierarchical zero-knowledge proof system. The first layer will be prover efficient (customized circuit optimization and hardware efficient proving algorithm). The second layer will be verifier efficient (succinct proof and EVM-friendly verification algorithm). Compared to all existing solutions, it has potential to support program even larger than EVM and more features like privacy.

• We will elaborate more for each one in the following articles. Each bullet-point will link to an article. If the link is not there, then it means “coming soon”!

  • Introduction to zkEVM

  • More technical details of zkEVM

  • Introduction to Layer-2 proof outsourcing

  • More technical details of Layer-2 proof outsourcing

  • Introduction to proof system upgrade

  • More technical details of the trade-offs between different proof systems