Methods comprising: contacting a carbon fiber seed to a carbon-metal melt, drawing the carbon fiber seed to form a carbon fiber. And, systems and apparatuses comprising: a carbon fiber reactor for fabricating carbon fiber, the reactor comprising a receptacle for containing a carbon-metal melt, and a plurality of nozzles through which a plurality of menisci are formed by the carbon-metal melt for contact with a carbon seed to fabricate the carbon fiber.