This is a firmware for reprap single-processor electronics setups, but this particular fork is specifically suited for BQ printers.
Based on Marlin, from Erik Zalm, this firmware is a mashup between Sprinter, grbl and many original parts.
Marlin is published under the GPL license because I believe in open development. Please do not use this code in products (3D printers, CNC etc) that are closed source or are crippled by a patent.