Rc<RefCell<...>> / Arc<Mutex<...>> and borrowing or locking for micro-scopes, only exactly when you need the inner values, will get you pretty far when you're l

Rc<RefCell<...>> / Arc<Mutex<...>> and borrowing or locking for micro-scopes, only exactly when you need the inner values, will get you pretty far when you're looking to turn off your brain. Sometimes they're even the correct choice! It's not entirely frictionless, but it can get pretty smooth. Cell / Atomic* can be nice too.