Are talking about the "hotreloading" or the "hotpatching"? (There are two separate mechanisms) The hotreloading just does RSX and assets, and is very fast, the hotpatching is a recompile (no getting around compiling Rust code), but it should be a faster one, and in many cases it should be able to maintain application state.

I've been able to get the hotpatching to work for use cases like "extract some UI code" into a new component that didn't exist before.

Note that the hotpatching is not enabled by default, you have to specify --hotpatch when running dx