Raspberry PI Akka Cluster LED strips

Ever since Eric Loots from Lightbend first showed me the Raspberry-PI based Akka Cluster with special LED stripes, I’ve wanted (at least) one of them. This is a 5 node cluster with …

2018: year in review

I had intended to write a yearly review for a few years now but have not managed so far – 2018 is going to be the year that I finally get down …

Akka anti-patterns: too many actors

Update 07.08.2018: clarified optimal vs. suboptimal use cases of having many actors at runtime (it could have been misunderstood that Akka isn’t meant to build systems with many actors – it entirely …

Tour of Akka Cluster

Here’s an overview of the Tour of Akka Cluster article series: Tour of Akka Cluster – Akka Distributed Data Tour of Akka Cluster – Eventual consistency, persistent actors, message delivery semantics Tour …

Akka anti-patterns: Java serialization

Akka makes use of serialization when messages leave the JVM boundaries. This can happen in mainly two scenarios: sending messages over the network when using Akka Cluster (do not use Akka Remote …

Akka anti-patterns: stateless actors

Actors are object-orientation done right (as opposed to say, objects in Java): their state is not visible from the outside and they communicate via messages. There’s no way to break encapsulation because …

A quick tour of build tools in Scala

Update 20.04.2018: added Polyglot Maven Scala has a rich ecosystem and active community producing a lot of useful libraries. So much so that, sometimes it is not easy as a newcomer to …

Akka anti-patterns: overusing ActorSelection

Akka’s ActorSelection makes it possible to look up actors by logical path in the hierarchy:

This selection can then be used like ActorRef in order to send messages to it using …