We will start by adding an Akka dependency into the build.sbt file of an empty Scala SBT project:
libraryDependencies += "com.typesafe.akka" %% "akka-actor" % akkaVersion
The akkaVersion could be looked upon the Akka website. At the time of writing this book, it was 2.5.13, so we would prepend val akkaVersion = "2.5.13" to the preceding snippet.
The SBT can create a minimal Akka project for you via a giter8 template: sbt new https://github.com/akka/akka-quickstart-scala.g8.
Now, we can instantiate an ActorSystem, which is the place where Akka's actors live:
import akka.actor._
val bakery = ActorSystem("Bakery")
Avoid defining multiple actor systems in the same JVM or even on the same machine. An actor system is not very lightweight and is usually configured to closely reflect the hardware configuration it is running on. Thus, multiple actor systems will not only consume more resources than needed but, in the worst case, they will compete for these resources.
It is also possible to create a default actor system without providing a name, but it would be best if you don't do this. Naming the actor system and actors will make your life easier while you reason about it and debug existing code.
As a next step, let's define an actor.