Being familiar the architectural pattern of strict separation of code and schema to ensure long term scalability/maintainability as more statement and table types are added.
Other than that, just basic understanding of how HTTP servers and load balancing works (eventually I can see us taking the python piece and turning it into its own load balanced service depending on volume, so someone who understands how to horizontally scale a web service would be a potential plus long term, but that would be more of a nice to have)