1. What is a Connector?

MMI Staking is a web service that "talks" with staking providers through a specific and common REST API, defined by MMI.

In order for it to talk with your existing API, you need to implement and host a Connector: a REST web service that sits between MMI Staking and your existing API, and that stands as an integration layer.

Initiating a stake or batch stake

The user initiates a stake or a batch stake from the MetaMask Institutional Portfolio Dashboard. This makes a POST /stakes to MMI Staking, it forwards the request to your Connector, that then calls your existing API, in order to build and return the deposit payload (the transaction data).

Once the dashboard receives the deposit payload, it opens it in the MetaMask Institutional extension via a JSON-RPC call, for the user to confirm and send to its custodian. More details about this flow here.

Supported EVM networks

• In production, your Connector must support Ethereum Mainnet (ChainID 1) only.
• In development, your Connector must support Holesky (ChainID 17000) only.

Implement this OpenAPI specification

To be compatible with MMI Staking, your Connector must support the above features, and expose them through this OpenAPI Specification.