What I meant above is that ideally we figure out an easy way for people to choose their database type and then have Zipkin pull in the required dependency for that database. So you would say you wanted to use SQLite or MySQL instead of Cassandra or whatever, and then you'd load the SQLite or MySQL dependency instead of the Cassandra dependencies. But I haven't looked into how to do that yet or even if there's a straightforward way to do it easily. In the mean time, I'm just including SQLite directly so there is something to test with.