TL;DR:

  There once was a ledger at Uber
  On DynamoDB it ran like a dream,
  Fast writes at great scale,
  But costs set sail,
  And consistency wasn't what it seemed.

I could not work "find someone to fire" into it, but I did not try that hard to be honest. I would not like to work with someone who'd leave a blameless postmortem with "those as asshats wouldn't apportion blame" tale to tell their smug crew later.