I've got a little app that successfully uses Tokio's Command to run subprocesses and all of that works beautifully. But I'd like to run these in a different systemd slice. I've found crates that work with std:
The Tokio Command type implements From<std::process::Command>, so if that library is able to construct an std Command object with the desired properties, you can simply convert it to a Tokio command.
That crate seems to work with raw cgroups, not with systemd slices specifically. You'll have to interact with systemd, not just with the kernel's cgroups APIs, if you want that. Furthermore, that crate only seems to support legacy cgroups v1.