It's overkill until it's not. We chose etcd initially but after a while we started wanted to ask questions about our data that weren't necessarily organised in

It's overkill until it's not. We chose etcd initially but after a while we started wanted to ask questions about our data that weren't necessarily organised in the same way as the key/value hierarchy. That just moved all the processing to the client, and now I just wish we used a SQL database from the beginning.