RailsAdmin vs. dat vs. ReactiveMongo

RailsAdmin is a Rails engine that provides an easy-to-use interface for managing your data.

Dat is an open source project that provides a streaming interface between every file format and data storage backend.

ReactiveMongo is designed to avoid any kind of blocking request. Every operation returns immediately, freeing the running thread and resuming execution when it is over. Accessing the database is not a bottleneck anymore.