Metamaterial is engineered material with exotic properties not found in nature. We explore computer-directed assembly of building blocks such as 0D, 1D and 2D nanostructures into complex architectures to develop programmable metamaterials for any desired functions and applications. We have invented a series of optothermal tools for the low-power digital assembly of colloidal particles. Inline metrology enables in-situ structural and functional measurements. We further couple metamaterials with functional molecules for biointegration and bioapplications.