The unprecedented rise of startups such as Google or Amazon has spurred an ongoing debate on the conceptualization of the corporate model these firms represent. Thus far, attention has centered on the analysis of their product and market strategies highlighting their platform nature as common feature and its defining characteristic. By applying and scaling the platform business model these companies have been able to capture value created outside the firm. The focus on the platform nature and the evolution of their external ecosystems, however, has left the work that is done inside these companies to create and provide online platforms largely unnoticed. Against this background, the article seeks to contribute to the debate by analyzing the inner mode of production as an essential component of their corporate model. The second nature of online platform firms, it is argued, is that they are tech companies. Building on this, the article aims to reconstruct how as tech companies they have learned and perfected to continuously develop and operate the internet applications that power their online platforms at global scale.