We pursue in-situ cultivation to access the vast diversity of microbes that remain unculturable by traditional laboratory methods—often referred to as "microbial dark matter." By growing environmental microbes within their extremophillic conditions using specialized devices biofabricated in-house, we can more accurately replicate their natural habitats and ecological interactions. This approach dramatically increases our ability to isolate novel strains, many of which produce unique secondary metabolites with untapped therapeutic potential. In-situ cultivation is essential to expanding the microbial repertoire available for natural product discovery.