hermez-core

Hermez Core is a Go implementation of a node that operates the zkEVM Hermez Network.

About the zkEVM Hermez Network

Since this is an implementation of a protocol it's fundamental to understand it, here you can find the specification of the protocol.

The protocol defines three phases of development, the repo currently implements:

• v1.3: almost fully implemented
• v1.5: WIP
• v2.0: WIP

Note that in terms of feature set, v1.5 and v2.0 are the same from the point of view of the node.

Architecture

It's important to note that currently this implementation is a monolith monorepo, but this is very likely to change in the near future.

The diagram represents the main components of the software and how they interact between them:

• RPC: interface that allow users (metamask, etherscan, ...) to interact with the node. Fully compatible with Ethereum RPC + some extra endpoints specifics of the network.
• Pool: DB that stores txs to be selected/discarded by the sequencer
• Sequencer: get txs from the pool, check if they are valid by processing them using the state and group a sequence of txs into a batch that then sends to Ethereum using the etherman. The goal of the sequencer is to maximize profit extracted of the txs gas fees, as described in the PoE protocol.
• Etherman: abstraction that implements the needed methods to interact with the Ethereum network and the relevant smart contracts.
• Synchronizer: Updates the state by fetching data from Ethereum through the etherman.
• State: process txs using the EVM and the Merkletree, and manage all the metadata (batches, events, receipts, logs, ...).
• Aggregator: consolidates batches by generating ZK proofs. To do so it gathers the necessary data that the prover needs as input. Once the prove is generated it's sent to Ethereum through the etherman.
• Prover: service that generates ZK proofs. Note that this component is not implemented in this repository, and it's treated as a "black box" from the perspective of the node. The prover has two implementations: JS reference implementation and C production ready implementation.

Development

It's recommended to use make for building, testing the code, ... Run make help to get a list of the available commands.

Requirements

• Go 1.16
• Docker
• Docker Compose
• Make
• GCC