Abstract: Modular additive manufacturing systems, related methods for simultaneously building three-dimensional parts in successively bonded layers, and related computer readable storage medium. A plurality of build assemblies is laid out along at least one direction of a manufacturing path defining a loop, and at least one build assembly is functioning to build a three-dimensional part from build material according to build instructions. A guidable module is guided via a guiding assembly along the manufacturing path to repeatedly perform at least one step necessary to build the three-dimensional part on each functioning build assembly.