I think it's about delaying the side-effect until `transaction.commit()`, and implementing as much of the business-logic as possible to happen inside the transa

I think it's about delaying the side-effect until `transaction.commit()`, and implementing as much of the business-logic as possible to happen inside the transaction. Virtual worlds (a model of the real world) could also be useful. Like, let the side effect run in the virtual world and let me inspect that virtual world. Here, "me" could be a programmer figuring out how to code against your API, or some ML thing trying to figure out how to make two APIs talk to one another.