I think Forth is much more suitable here. You can implement a lot of features in 512K. You can extend the code (and language!) at runtime, you can debug remotely, and do other nice things.
These Rust trolls (at least I hope, for your sake, that you are trolling here and not serious) are getting annoying.
One would wonder how we managed to cope before Rust.
Also, you should ask these guys [1] [2] how they know they're using memory safely. Has Rust ever been used to fly aircraft and fricking space shuttles? I didn't think so.