GMACS: a wide-field, moderate-resolution spectrograph for the Giant Magellan Telescope

We discuss the latest developments of a spectrograph for the Giant Magellan Telescope. The instrument is designed to provide high throughput, moderate resolution, optical spectra for the telescope and be capable of flexible and rapid reconfiguration. The focal plane can be populated with custom slit masks or multiple fibers, allowing for observations of multiple objects simultaneously.