Overview
ZKsync Gateway is an optional settlement aggregation layer for ZK chains, including both rollups and validiums. It is purpose-built to enhance interoperability, provide proof aggregation, and offer cost efficiencies for chains that choose to settle on top of it.
As a settlement aggregation layer between ZK chains and Ethereum, ZKsync Gateway collects proofs from multiple chains and submits them to Ethereum for final verification. This reduces gas costs for proof verification while preserving Ethereum as the root of trust.
Assets on Gateway-settling chains remain locked on Ethereum, and all L1-to-L2 interactions—such as deposits—are still executed from Ethereum, not from Gateway.
Key Benefits
- Interoperability: Enables faster communication between ZK chains settling on Gateway, without affecting direct L1–L2 connectivity from Ethereum.
- Proof Aggregation: Reduces costs for users and chains by aggregating multiple proofs into a single proof submitted to Ethereum.
- Cost Efficiency: Offers stable pricing for proof verification compared to direct settlement on Ethereum, while still maintaining Ethereum-based asset security.
Governance
ZKsync Gateway was whitelisted as a settlement layer in the ZIP-10 governance proposal. This proposal allows chain operators to select ZKsync Gateway as their settlement layer in place of Ethereum.
Migration to ZKsync Gateway is optional, and chains initially launch with Ethereum settlement. If desired, operators may later configure their chain to use Gateway as the settlement layer. Switching between Ethereum and Gateway is supported at the protocol level, but a chain must first be deployed with Ethereum as its origin settlement layer.
Gateway Network Details
| Environment | Chain ID | Gas Token | Explorer |
|---|---|---|---|
| Testnet | 506 | $ZK | Testnet Explorer |
| Mainnet | 9075 | $ZK | Mainnet Explorer |