Akka is a
source-available
Source-available software is software released through a source code distribution model that includes arrangements where the source can be viewed, and in some cases modified, but without necessarily meeting the criteria to be called open-source ...
toolkit and runtime simplifying the construction of concurrent and distributed applications on the
JVM
A Java virtual machine (JVM) is a virtual machine that enables a computer to run Java programs as well as programs written in other languages that are also compiled to Java bytecode. The JVM is detailed by a specification that formally describes ...
. Akka supports multiple programming models for concurrency, but it emphasizes
actor-based concurrency, with inspiration drawn from
Erlang.
Language bindings exist for both
Java
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's List ...
and
Scala. Akka is written in Scala and, as of Scala 2.10, the actors in the Scala standard library are deprecated in favor of Akka.
History
An actor implementation, written by Philipp Haller, was released in July 2006 as part of Scala 2.1.7. By 2008 Scala was attracting attention for use in complex server applications, but concurrency was still typically achieved by creating threads that shared memory and synchronized when necessary using locks. Aware of the difficulties with that approach and inspired by the
Erlang programming language's library support for writing highly concurrent, event-driven applications, the Swedish programme
Jonas Bonércreated Akka to bring similar capabilities to Scala and Java. Bonér began working on Akka in early 2009 and wrote up his vision for it in June of that year.
The first public release was Akka 0.5, announced in January 2010. Akka is now part of the Lightbend Platform together with the
Play framework
Play Framework is an open-source software, open-source web application framework which follows the model–view–controller (MVC) architectural pattern (computer science), architectural pattern. It is written in Scala (programming language), Sc ...
and the
Scala programming language.
In September 2022, Lightbend announced that Akka would change its license from the
free software license
A software license is a legal instrument (usually by way of contract law, with or without printed material) governing the use or redistribution of software. Under United States copyright law, all software is copyright protected, in both source ...
Apache License 2.0 to a