The Miniworldmaker now has version 1.0! (strictly speaking already 1.0.3) That doesn’t mean that it’s bug-free (I’ve actually fixed a few minor bugs) or you won’t encounter unexpected problems - I’ll have a lot of work to do next year. But now the API looks exactly the way I want it to. Physics Objects of a class are now physically simulated if the method setup_physics() is implemented in the class.