MultiGov Architecture

MultiGov employs a hub-and-spoke model to enable cross-chain governance, utilizing Wormhole's interoperability infrastructure for secure cross-chain communication. This architecture allows coordinated decision-making across multiple blockchain networks while maintaining a central coordination point.

Key Components

Hub Chain Contracts

The hub chain is the central point for managing proposals, tallying votes, executing decisions, and coordinating governance across connected chains.

• HubGovernor - central governance contract managing proposals and vote tallying
• HubVotePool - receives aggregated votes from spokes and submits them to HubGovernor
• HubMessageDispatcher - relays approved proposal executions to spoke chains
• HubProposalExtender - allows trusted actors to extend voting periods if needed
• HubProposalMetadata - helper contract returning proposalId and vote start for HubGovernor proposals
• HubEvmSpokeAggregateProposer - aggregates cross-chain voting weight for an address and proposes via the HubGovernor if eligible

Spoke Chains Contracts

Spoke chains handle local voting, forward votes to the hub, and execute approved proposals from the hub for decentralized governance.

• SpokeVoteAggregator - collects votes on the spoke chain and forwards them to the hub
• SpokeMessageExecutor - receives and executes approved proposals from the hub
• SpokeMetadataCollector - fetches proposal metadata from the hub for spoke chain voters
• SpokeAirlock - acts as governance's "admin" on the spoke, has permissions and its treasury

System Workflow

The MultiGov system workflow details the step-by-step process for creating, voting on and executing governance proposals across connected chains, from proposal creation to final cross-chain execution.

1. Proposal creation:
   • A user creates a proposal through the HubEvmSpokeAggregateProposer, which checks eligibility across chains, or directly on the HubGovernor via the propose method
   • The proposal is submitted to the HubGovernor if the user meets the proposal threshold
2. Proposal metadata distribution:
   • HubProposalMetadata creates a custom view method to be queried for use in the SpokeMetadataCollector
   • SpokeMetadataCollector on each spoke chain queries HubProposalMetadata for proposal details
3. Voting process:
   • Users on spoke chains vote through their respective SpokeVoteAggregators
   • SpokeVoteAggregators send aggregated votes to the HubVotePool via Wormhole
   • HubVotePool submits the aggregated votes to the HubGovernor
4. Vote tallying and proposal execution:
   • HubGovernor tallies votes from all chains
   • If a quorum is reached and there are more for votes than against votes, the vote passes and is queued for execution
   • After the timelock delay, the proposal can be executed on the hub chain
   • For cross-chain actions, a proposal should call the dispatch method in the HubMessageDispatcher, which sends execution messages to the relevant spoke chains
   • SpokeMessageExecutors on each spoke chain receive and execute the approved actions through their respective SpokeAirlocks

Cross-Chain Communication

MultiGov relies on Wormhole's infrastructure for all cross-chain messaging, ensuring secure and reliable communication between chains. Wormhole's cross-chain state read system, known as Queries, is used for vote aggregation and proposal metadata. Additionally, cross-chain proposal execution messages are transmitted through Wormhole's custom relaying system, enabling seamless coordination across multiple blockchain networks.

Security Measures

• Vote weight window - implements a moving window for vote weight checkpoints to mitigate cross-chain double voting
  • Proposal extension - HubProposalExtender allows for extending voting periods by a trusted actor in the case of network issues or high-stakes decisions
• Timelock - a timelock period between proposal approval and execution allows for additional security checks and community review
• Wormhole verification - all cross-chain messages are verified using Wormhole's secure messaging protocol

Detailed Architecture Diagram

This architecture ensures that MultiGov can operate securely and efficiently across multiple chains, allowing for truly decentralized and cross-chain governance while maintaining a unified decision-making process.