So the user has this web interface to maintain projects, groups of rules - including a validity from/until - plus rules and actions.
The rules are there to check the data and the actions are a means to modify the data based on the results of the rules. E.g. one can evaluate if field 1 is greater field 2 and if this is the case set field 3 to a certain value. The user has possibilities to concat fields, to append/prepend values or to do mathematical or date calculations. The system is open to allow developers to extend this functionality according to their requirements. THat is also true for the rules.
Once a set of rule groups, rules and actions is complete, one can download or export a zip file and use this zip file in Pentaho PDI to run the rules and actions against the data.
The rule engine can also run standalone, can be integrated into a web application or java application. I have also included functionality to run it as a socket server, which waits for incomming connections. Finally it is of course also possible to run the rule engine in a docker container (http://docker.io).
So a complete set of tools is available to the community: the rule engine, a Pentaho Plugin for PDI and an interface for the developer and/or business user to easily define rules and actions.
Everything is open source and I would like to invite everyone to give it a try and send feedback.