Distributed applications are traditionally developed using separate modules for each component in the distributed system, which can even be written in different programming languages. Those modules react on events such as user input or network messages and may in turn produce new events to be handled by different modules. Applications which define their runtime behavior based on their reaction to events are called reactive. Distributed event-based data flow makes it is hard to reason about the system and therefore makes the development of distributed systems challenging.

In this paper, we present ongoing research on RETier, a language for distributed reactive programming. The language eases the development of distributed reactive systems by providing a coherent model to reason about the system and supporting various distributed architectures through dedicated language abstractions.