chain.link_before(Write::::one(Box::new(engine)));
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait persistent::PersistentInto<std::sync::Arc<std::sync::Mutex<std::boxed::Box<engine::SemanticEngine + std::marker::Sync + std::marker::Send + 'static>>>> is not implemented for std::boxed::Box<E>
chain.link_before(Write::::one(Box::new(engine)));
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait
persistent::PersistentInto<std::sync::Arc<std::sync::Mutex<std::boxed::Box<engine::SemanticEngine + std::marker::Sync + std::marker::Send + 'static>>>>
is not implemented forstd::boxed::Box<E>