In this episode Nick Greenfield, the founder of One Codex, discusses his transition from a background in environmental studies and international relations to establishing a microbiome company. He touches on his experience entering a contest by the Defense Threat Reduction Agency in 2013, aimed at developing better metagenomics algorithms. Despite not winning, the positive feedback on their prototype’s ease of use revealed a market gap. This led to the creation of One Codex. Greenfield further expostulates on the challenges and lessons learned during the construction of the first metagenomic database for One Codex.