Hi, I‘m working on a robotics bare-metal OS for Raspberry Pi, maybe it‘s worth a look.
It contains several crates for the time being and the final OS might look different from the crates base to what actual developer would need to develop on top of it :)

It‘s still a long way to go compared to other already complete OS‘es but I‘d appreciate your opinion - even if this stage of the crates could also be used for any purpose OS...

Thx in advance.
Appreciate your efforts in looking into those things.