Nature Materials, Published online: 01 July 2025; doi:10.1038/s41563-025-02250-6A resin comprising a hybrid epoxy–acrylate monomer and wavelength-selective photosensitizer components achieved rapid, high-resolution 3D printing of multimaterial structures. This technique produced structures that emulate natural mechanical gradients and functional structures including a spring for compressive damping, a knee joint model for smooth motion and a stretchable substrate for wearable electronics.