1. A device comprising: an extruder having an interior chamber that receives a build material for extrusion, a nozzle that extrudes the build material, and a motor that drives the build material through the interior chamber and out the nozzle; a build platform that receives an object formed of the build material extruded from the nozzle; a positioning assembly that positions the build platform relative to the extruder; and a controller coupled in a communicating relationship with the extruder and the positioning assembly, the controller programmed to impart a non-uniform surface texture to an exterior wall of the object by varying a deposition rate of the build material onto the object during fabrication of the exterior wall.