Klipper

Klipper is the Open Source 'firmware' ecosystem that controls the printer. It's designed to make use of small systems and SoCs as linux hosts that run its series of distributed applications and services which APIs, UIs and connects to one or more microcontrollers. This replaces the Marlin firmware style systems that used to be prevalent for 3D printer control and greatly improves in the following areas:

See http://klipper.org