It's a platform for managing a kind of appointment, but it doesn't have an appointments table. The appointments data is combined with a different table, and there was no way to disentangle them easily because the entire system was built around that object model. Case study in failure to normalize.

The hard part is done, but basically we had to switch the engine while the car was running so to speak. In order to switch this out you need to start writing the correct data shape, then switch everything over to reading that shape. When people work strict 9 to 5s this will take you forever especially when managing a large amount of volume, which requires you to be extremely risk-averse and slow.