A library for storing a cartridge of data-storage media includes a removable module and a chassis having a module receptacle. Cartridge storage slots arc disposed within the chassis, and a media drive is disposed within the removable module. A cartridge transporter is disposed within the chassis and transports the cartridge between one of the cartridge slots and the media drive when the module is inserted within the module receptacle. A library control circuit is disposed within the chassis and controls the cartridge transporter. An interface circuit is disposed within the removable module and electronically interfaces a host computer to the media drive, and, when the removable module is inserted within the module receptacle of the chassis, electronically interfaces the host computer to the library control circuit.