The Four Opens are a set of principles guidelines that were created by the OpenStack community as a way to guarantee that the users get all the benefits associated with open source software, including the ability to engage with the community and influence future evolution of the software.
Under these guidelines, the OpenStack community grew from tens of contributors to thousands, creating one of the top three most active open source projects in the world behind the Linux Kernel and Chromium. The Four Opens were instrumental not only in this success but also in building a thriving, global community.
We at OSF consider The Four Opens our guiding principles in everything we do.
How we practiced the Four Opens has evolved over time and incorporates many practices: public code reviews, design summits, technical committee, and lazy consensus. Earlier this year, the OpenStack Foundation started the Four Opens Book as a way to share these learnings and how the Four Opens were initially intended for upstream, and how they proved applicable to downstream activities such as user feedback gathering, marketing, or event management. As the OpenStack Foundation grows to more generally support Open Infrastructure, the Four Opens will grow alongside it.