Support for STM32 Nucleo?

save()

So page sizes on F4xx chips go: 16,16,16,16,64,128,128,128

As you have enough flash, you just want to stick code at the end in a single 128kB page (like for the F4DISCOVERY). I think using the py file arrangement from that (Eg, no saved_code structure) should 'just work'.

You can always use peek32 to check if the code is in the correct place after saving it.

I think it could just be aliasing Arduino's names to Espruino's names...
Yes, I think that's all you'd want to do.