gzbl

Gzbl is an open-source G-code interpreter and CNC control program designed for Unix-like systems. It translates standard G-code commands into motion instructions for motor systems and typically runs on a host computer that communicates with a microcontroller or motion controller over a serial link. gzbl provides a compact, portable alternative to firmware-oriented solutions, emphasizing simplicity, configurability, and use on hobbyist hardware.

The software comprises a lightweight interpreter, a basic motion planner, and a protocol for host-PC communication. It supports common G-code commands used in milling and cutting workflows, including linear (G1) and arc (G2/G3) moves, feed rate control, and machine-state commands. It also offers options to configure work coordinate systems, limit checks, and basic spindle or laser control, within the capabilities of the connected hardware.

gzbl is typically used by connecting a host PC or single-board computer to a dedicated motion-control board or microcontroller. The host streams G-code to gzbl, which then drives the hardware interface according to the parsed instructions. The project is maintained as open-source software with a public repository, contributing guidelines, and documentation that cover installation, configuration, and common hardware setups.

In the CNC community, gzbl is viewed as a lightweight alternative to more feature-rich firmware and controller stacks, suitable for small-format machines such as hobbyist routers, laser cutters, and engravers. See also: GRBL, LinuxCNC, TinyG, and other G-code interpreters.