I love the idea of bare-metal ports to the Pi. I saw snakeware posted here not too long ago. Are there other examples? ColorForth would be interesting as well
In addition to the Interim Lisp system I mentioned in another comment, there are a number of bare-metal applications for the Raspberry on github (mostly ports of games).
Could someone share what one gains with such 'baremetal' ports? I see only the loss of common ground, well tested libraries and functionality.
It doesn't take a lot of Linux know-how to boot you favorite interpreter from /etc/rc.local or replacing /sbin/init (losing the libraries again, but at least keeping the kernel with the filesystem, network support and all the hardware drivers).
In general, lower code complexity results in fewer bugs and security problems, less code implies lower resource usage, so you could run the system with a smaller main memory, a slower CPU or lower power/energy consumption. In addition, if you plan to target real-time applications, setting up Linux to guarantee your real-time constraints is not trivial.
All of this is not that relevant for running Smalltalk-80 on the Pi, since Smalltalk was running happily on 16-bit machines with one or a few MBs of RAM.
So I guess the ultimate reason for doing this is "it can be done" - for the fun of hacking :-).
