We have designed a platform technology for producing specific biosensor libraries and enzymes with unique reaction kinetics. Our Enzyme Positional Activity Substrate Scan (EPASS) platform scans enzymes and produces heat maps of an enzyme’s active site residues and of substrate specificity sites.  A single-day EPASS run will enable fine-tuning of enzymes for increased activity and substrate specificity through a simultaneous, massively parallel, in silico– and in vitro-directed evolutionary approach to enzyme engineering.