Mixxx is a digital DJ system, where Wave, Ogg, FLAC and MP3 files can be mixed on a computer for use in live performances. Filters, crossfader, and speed control are provided. Mixxx can sync the 4 decks automatically, using an algorithm to detect the beat. Mixxx works with ALSA or Jack, can be controlled from the GUI or from external controllers, including MIDI devices and joysticks, and supports skins.