The field of soil bio-improvement, through microbial-induced calcite mineralization, has gained significant momentum in scientific literature in the past years. The phenomenon, which is inspired from natural environments, has been extensively applied at laboratory bench-scale, leading to a surge of expectations around its potential fit as a mainstream solution to real-world construction and environmental problems. The present study aims to break out of the laboratory and deliver a benchmark, large-scale application of ground bio-reinforcement which was designed and implemented in the canton of Vaud, Switzerland. The work aims to mitigate landslide risk in a slope hit by extreme rainfall in early 2018. This resulted in increased pore water pressure within the failure surface, therefore reducing the soil’s effective shear strength and triggering the slip of roughly 3,000 cubic meters of earth mass. A grouting solution was designed to induce the bio-mineralization of calcite binders within the targeted slip zone. In order to present obtained results in the best possible light, we combine laboratory tests, in situ monitoring, microstructural inspections, and post-stabilization aerial surveillance. Obtained data reveal slower displacement rates for the bio-stabilized zone compared to the rest of the slope. Overall, our global analysis aims to offer new prospects towards bio-mediated geotechnical practice under real-life conditions.