Declare is currently being redesigned and integrated into CPN Tools. This means you can extend the tool (see, e.g., http://westergaard.eu/2012/11/demo-of-simulator-extensions-in-cpn-tools-4/). We are never going to become like YAWL. YAWL is overly complex, and in my view requiring a web application container just to do experiments is not a viable way to go for research. It may be necessary for real deployment, but we are doing experiments and need something that allows to quickly prototype idea, and the simpler solution here is that.

I’m eager to construct my own declarative workflow system by using parts of “Declare” system, e.g. LTL parser or checker (if any). So, I’m curious why “Declare” cannot release its source, or even better, make it self like “YAWL” whereby I could build my own declarative workflow system (when I say use it to build my own workflow system, I don’t want to simply use “Declare” per se, rather, I want to do hard coding by invoking related APIs …)