In this demo, we present the programming style for distributed applications using ScalaLoci, which provides mechanisms to abstract over common tedious and error-prone issues of distributed systems development, reaching from low level communication to higher level event-based interaction.

The language allows a distributed program to be developed as a single code base generating the code specific to each component of the distributed system – including communication code – automatically during compilation (multitier approach). In ScalaLoci, data flow between the components of the distributed system is specified explicitly (reactive approach).

First, ScalaLoci provides “placement types” to associate data and computations to locations. Developers can control the placement by representing the different components of the distributed system at the type level. In contrast to existing multitier languages, our solution allows to go beyond the Web domain and the client–server model and enables static reasoning about placement. Second, we support “multitier reactives” – placed abstractions for reactive programming – which let developers compose data flows spanning over multiple distributed components.