I made some quick tests for filesystem store and it works a charm. Sessions are persistent after a server restart.
On the default config the fs store will store in /sessions the session files.
There are some changes needed to some core files(that could be rewritten in the future) so I am hoping they can add it soon to the core. (@george)
Additionally, as FS store won’t work on hosting providers with non-persistant storage(like Heroku) it is important also to offer an alternative. I will probably conduct some testing later on for the knex db driven session store. Both options seem to be quite straightforward.