Nature fabricates biominerals with adaptable properties and morphologies. Inspired by the biological reductionist strategy, we develop a drop-based additive manufacturing technique that enables building CaCO3-based composites with hierarchical structures and adaptable mechanical behaviours. By controlling the design and assembly of small modules, our 3D printed porous biominerals possess the nanoscale structure control through biomineralization and the microscale porosity through the control over capsule compositions and dimensions. The bioinspired approach we develop could also apply to other biominerals like hydroxyapatite or magnetite to meet the future demands of sustainable biomedical materials.