Boojum, the latest proof method for zkSync Era, has undergone an upgrade to transition to a STARK-boosted proof method, enhancing decentralization significantly. This upgrade enables high-level functionalities on standard consumer hardware.

Boojum, a Rust-based cryptographic library, is pivotal for executing scaled versions of ZK circuits for both ZK Stack and zkSync Era. It was designed to achieve cryptographic scalability without compromising user experience or requiring disruptive resets.

From the outset, zkSync's goal has been to promote individual freedom by democratizing self-ownership through a trustless, permissionless, secure, cost-effective, and user-friendly blockchain network. Boojum's advanced capabilities contribute to this vision while reducing hardware requirements for decentralization.

The team has been diligently working on this upgrade, currently in the process of deploying it on Mainnet. The architecture of zkSync Era was meticulously designed to enable scalable segments, including the proof method.

To facilitate scalability, Merkle tree data structures were employed to store network status information, with Blake2s serving as the adaptable hash function. Scaling the proof method simply requires re-executing Blake2s in-circuit.

Extensive external and internal audits, along with rigorous automated and manual testing, were conducted during the development of zkSync circuits and the Boojum arithmetization library.

Currently, both the new and previous proof methods are undergoing testing, including the creation and verification of shadow proofs for Mainnet blocks. Once validated, migration considerations will arise, with Boojum playing a crucial role in advancing a secure, upgradable, and efficient zkEVM.