Thanks. Simplicity was the main goal and I took many passes eliminating cruft. The initial plans for persistence is to disk, in the form of a Command Log. Similar to VoltDB's Command Log or Redis' AOF. A simple approach to durability.
There will be some sort of interface for the storage. I'll keep in mind pluggability. It is something Gearman had back in the day also[0]. Most likely it will be persistence to disk for some time and once more clarity comes out, possibly pluggability.