As for the MNT Reform, the only thing I’m not sure is open is the actual processor firmware, but the schematics for its usage are available and even the Wifi firmware is open, so there remains the problem of actually verifying the hardware you get is actually the hardware you ordered, but that is a bit more complicated I think.
As of August 2023, the best way to avoid the problem of
AFAIK Is using an MNT Reform With GNU Guix as its OS, I really liked this article “The Full-Source Bootstrap: Building from source all the way down”. This approach could, potentially, solve the problem of the untampered compiler. Damn, maybe it already does.
As for the MNT Reform, the only thing I’m not sure is open is the actual processor firmware, but the schematics for its usage are available and even the Wifi firmware is open, so there remains the problem of actually verifying the hardware you get is actually the hardware you ordered, but that is a bit more complicated I think.