Soft Hardware, Flowing Software: Reconfigurable Microfluidics for Adaptable Chemical Computation.

Chemical and physical computing systems promise information processing in performance regimes inaccessible to conventional electronics. However, they are typically constrained by static hardware architectures that limit adaptability and computational richness. Here, we introduce a reconfigurable microfluidic platform where soft hydrogel structures are 3D-printed and erased in situ to dynamically reshape the physical environment in which chemical computation occurs. By treating microfluidic geometry as an active, programmable element rather than a passive container, we demonstrate hardware-reconfigurable control over chemical information processing. We demonstrate switchable Deoxyribonucleic acid (DNA) logic gates that alternate between AND and OR functionality without modifying the underlying reaction network, decoupling logic function from molecular composition. Extending this to a non-equilibrium chemical reaction network in the form of a feedback-controlled pH oscillator, we demonstrate that printed structures steer reaction kinetics and spatial pattern formation, giving rise to geometry-dependent spatiotemporal states. Leveraging these dynamics, we implement a physical reservoir computer in which reconfigurable microfluidic hardware enables the realization of diverse nonlinear functions through simple linear readout. Our work establishes reconfigurable soft microfluidic hardware as a control layer for chemical computation, highlighting how adaptable physical environments actively expand the computational state space of chemical software.