klipper

Klipper is firmware for 3D printers, written primarily in C and Python. Firmware is the low-level software that runs on the electronics inside a machine and controls its physical movement. What makes Klipper different from most 3D printer firmware is its architecture: the computationally intensive work runs on a standard computer (like a Raspberry Pi) rather than on the small microcontroller chip inside the printer itself. The microcontroller only handles the time-sensitive signaling that actually moves the motors, while the heavier math and logic run where there is much more processing power.

This split approach means Klipper can run more complex motion calculations, update the motion plan faster, and expose configuration through plain text files rather than requiring you to compile new firmware every time you adjust a setting. If you want to change how your printer behaves, you edit a config file and restart the software.

Klipper supports a wide range of 3D printer hardware and is used as an alternative to the firmware that ships with commercial printers. It is popular in the hobbyist and enthusiast community, particularly on printers that people build or modify themselves. The full list of capabilities, supported hardware, and setup guides live on the project website at klipper3d.org rather than in the repository README itself.

Installation involves running the Klipper software on a host computer connected to your printer and flashing a small companion piece onto the printer's microcontroller. The project is free and open-source under a permissive license and is maintained with sponsor support.