If we are ever to have a permanent presence on Mars, we will have to learn to build there. Shipping the material from Earth to build something as simple as a pressurized habitat is prohibitively expensive, so we will have to make sure of the materials available on Mars’ surface. A research team led by Ning Liu at the Hong Kong University of Science and Technology recently published a paper in Chem Circularity that uses biology to do much of the heavy lifting for the structural materials we would typically use concrete for. If their method is adopted, we might quickly find another Earth-based lifeform in abundance on Mars - yeast.