Bacteria can be engineered to do all sort of useful things. A field that is gaining traction is using bacteria to build materials made of organic and inorganic components. Writing in Nature Biotechnology, Lingchong You and colleagues develop an approach that uses synthetic biology to assemble materials in a programmable manner. The authors use self-assembling bacteria to generate inorganic-organic structures by applying gold nanoparticles to the bacterial colonies. The geometry of the bacterial-made structures can be changed by altering the characteristics of the membrane the bacteria are grown on (pore size and hydrophobicity). Using this approach, the researchers make pressure sensors (and provide accompanying video of the result)