I literally just saw this a few minutes ago and when I saw it was fully open source I thought I should post it here! In addition, the fact that it's only 9 dollars (supposedly) means that handmade_hero could potentially be accessible to even extremely poor areas of the world.

As far as I can see it will run some kind of Linux as its standard OS. So by default HH Linux port already should be able to run there. As long as HH code will not depend exclusively for x86 architecture on Linux, it should expect x86, ARM or any other architecture. And because Allwinner A13 chip supports Neon on it's Cortex-A8 ARM CPU, that means RPi neon optimizations will work this CPU just fine.

The kickstarter project page claims that the system will be fully open source, but the GPU they chose, the Mali-400, is not as well documented as that of the Rpi and still needs a binary blob to work. The Lima project is an attempt at reverse-engineering the thing, but it's still a work in progress (and has been for some years). I think that limits it as the platform for the bare-metal port of Handmade Hero.

Also, the CPU has only one core and the HDMI board is sold separately (and brings the price to that of a Raspberry Pi).

And the SoC they use is Allwinner. They are know to violate GPL and not providing all the source code required: https://linux-sunxi.org/GPL_Violations