That's interesting; I imagine that they're not going to just wholesale replace std::sync::Mutex and the like with the parking lot versions due to the fact that at least last time I checked, doing that would cause breaking API changes (e.g. Mutex::lock not returning a Result, so are they planning on just making a separate module with the parking lot API as an alternative? (I supposed they could just make the parking lot Mutex return a Result that always returns Ok, but that doesn't really seem like it would appeal to most people).