Proxy Server
The WaaS SDK exposes a subset of the WaaS APIs to the mobile developer. While you can make all calls with the WaaS backend directly, Coinbase recommends that you proxy all calls except MPC operations.
Important
Coinbase recommends that you proxy all calls except MPC operations.
MPCOperations are the only APIs that require direct calls from WaaS, specifically:
initMPCSdk
bootstrapDevice
getRegistrationData
computeMPCOperation
A proxy server gives you more control and lets you:
- Perform end user authentication.
- Integrate with a push notification system
- Simplify rollouts of new features (server-gated)
- Log API calls and collect metrics.
- Filter results (for example, policy enforcement).
- Store API credentials (rather than exposing them to the client).
- Rate limit traffic.

Terminology:
- "Customer" refers to you, the developer who is coding using WaaS APIs.
- "End User" refers to the user of the application that you are coding.
- "Server" refers to a proxy server owned by you, the customer.
- "Application" refers to an iOS/Android app owned by you, the customer.