We are proud to release MongoFaker.

It is a small Scala Library which starts a MongoDB server in ~250ms.

All you have to do is supply some mongod executable inside your $PATH variable (on Debian/Ubuntu it is available automatically after installing mongodb), and you can start as easily as

import net.reactivecore._
val instance = MongoInstance.start(MongoConfiguration())
// MongoDB server up and running in a
// temporary test directory.
val port = instance.port
val address = instance.address
// Connect to port & address
// Test your code
instance.stop()

Hopefully it helps other developers saving some seconds on each integration test run.