The peer library gets embedded in your application server(s). It is a gateway to the rest of the database, submitting transactions and accepting changes from the transactor. It also provides data access, caching and query capability. It contains all the communication components needed for connecting to the transactor and storage services, as well as Datalog and other facilities for managing your data.
The peer library can act in standalone mode, using an in-memory database as a stand-in for the other components.
The peer library uses the Peer API.