This isn't true. You don't need a distributed sharded setup in order to scale. (You probably do if you are limiting yourself to MySQL) I built financial applica

This isn't true. You don't need a distributed sharded setup in order to scale. (You probably do if you are limiting yourself to MySQL) I built financial applications way back in the day that had a lot more reads and writes than twitter, and we just used ONE gigantic, super expensive database server.