The motherboard of a miner. Full Linux on a swappable compute module, documented I/O, and files you can build from or run as-is.
Libre Board is the 256 Foundation's open-source mining control board. A control board is the motherboard of a miner: it schedules power, cooling, and the network, and it talks to the hashboards. Libre Board runs a full Linux system on a swappable compute module, with the I/O brought out and documented.
It is both an open reference design and a board you can run as-is. The files are yours to build from, or to cut down to a smaller parts list and a different outline.
The compute module on the current design is a Raspberry Pi CM5, on the two standard 100-pin connectors. Mujina is the mining firmware. Ember One is the hashboard with first-class support, over USB-C. The same Linux system can run other software beside the firmware, such as a Bitcoin node or a local Stratum pool (Hydrapool).
Libre Board is part of the 256 Foundation open mining stack, with Mujina, Ember One, and Hydrapool.
The picture above is the front render from the design files. The back, with the Liberty mark in silkscreen, is below.
rev3. That branch becomes main once it is merged. See Design files.