REJO and ROS are built over Junior [4], a set of Java class that gives the facility to make a reactive programming. The REJO's programming model, which is close to that of Junior, provides reactive instructions that are executed in a reactive machine. The set of reactive instructions implements the instantaneous broadcast events as well as a logic parallelism operator which does not use threads. One of the particularities of Junior reactive instructions is that they have a formal semantic defined by rewriting rules.
The initial design of REJO and ROS began in the intership of R. ACOSTA[15] at ESSI and nowadays the system continue in develop. The first version used SugarCubes [9], a similar version to Junior without formal semantic. The current version of REJO only produces Junior code. This version meets the Jr interface which allows programmers to use any Junior implementation: Rewrite, Replace, Storm et Simple.
You can find more information of all these elements in the following links:
This work was supported by the Project Mimosa at INRIA and CONACYT.