The DECODE OS is a GNU+Linux distribution for private peer-to-peer networks of distributed computing. It is easily customisable and comes with an intuitive web application that facilitate the task of transforming Docker files (a popular format to prototype software application) into OS images ready to install on embedded and cloud infrastructure. This deliverable details the implementation details of DECODE OS as well provides operational guidelines to deal with its internals. As a demonstration, the web application is publicly available on toaster.dyne.org.