vil'mo

@andriyDev 1 and 2 - Those methods require exclusive world access. Sometimes it can matter. 3 - It's not as ergonomic as having a system runner that abstracts you out...

By the way, I've just managed to put the thought into text and `#[system]` macro is actually a good way to make [`run_system_cached`](https://dev-docs.bevyengine.org/bevy/ecs/prelude/struct.Commands.html#method.run_system_cached). If we do this ```rust run_system_cached(&mut World);...

@benfrankel `MySystem` can be not ZST. Look at the [implementation](https://dev-docs.bevyengine.org/src/bevy_ecs/system/system_registry.rs.html#381-385) of the function - it checks only the type that implements `IntoSystem`, but not the actual system It actually would...

> you mean if the system had no system state there would be no reason to cache it yes, that's what I meant