I was very much in favour of (abstract) state machines, especially the Rebel DSL that was developed in Rascal. A very nice thing about Rebel is that it can do

I was very much in favour of (abstract) state machines, especially the Rebel DSL that was developed in Rascal. A very nice thing about Rebel is that it can do (bounded) model checking using SMT solvers. Currently, I believe (Pure) Objects (with restrictions!) are a better approach because it doesn't require a paradigm switch. We already know them and they are also little state machines, right? If done right, we can also do explicit model checking etc, version control. Actors/Erlang/Akka is also a good choice, although they add some complexity compared to objects: it's hard to do synchronous calls with Actors for instance.