It is possible to run a complete operating system just from a flashdrive. As an alternative to using a Raspberry Pi computer to act as a server, you can write the CarpentriesOffline OS to a flashdrive and then boot your computer from the flashdrive. The CarpentriesOffline Os is built on Slax which, in turn, is built on Debian.
Step-by-step instructions for creating a CarpentriesOffline flashdrive